Polymerizable composition, and photosensitive layer, permanent pattern, wafer-level lens, solid-state imaging device and pattern forming method each using the composition

ABSTRACT

A polymerizable composition contains (A) a polymerization initiator that is an acetophenone-based compound or an acylphosphine oxide-based compound, (B) a polymerizable compound, (C) at least either a tungsten compound or a metal boride, and (D) an alkali-soluble binder.

This is a Continuation Application of U.S. application Ser. No.13/240,185, filed Sep. 22, 2011, which claims priority under 35 U.S.C.§119, from Japanese Application No. 2010-212886, filed, Sep. 22, 2010,the disclosures of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a polymerizable composition,particularly, a polymerizable composition suitably usable for theformation of a solder resist, and a photosensitive layer, a permanentpattern, a wafer-level lens, a solid-state imaging device and a patternforming method each using the composition.

2. Description of the Related Art

Conventionally, in the case of forming a permanent pattern such assolder resist, a photosensitive layer is formed on an objective memberby using a method of spin-coating a photosensitive composition in aliquid form, a screen printing method, a method of forming and drying acoated film according to a spray printing method, or a method of coatingand drying a photosensitive composition on a temporary support to obtaina laminate film having a photosensitive layer and transferring only thephotosensitive layer onto a member by means of a vacuum laminator or aroll laminator. As for the method to form a permanent pattern such assolder resist, there is known, for example, a method where aphotosensitive layer is formed by the method above on a silicon wafer onwhich a permanent pattern is formed, a silicon wafer having wiringthereon, or a substrate such as copper-lined laminate board, and thephotosensitive layer of the laminate is exposed, then developed to forma pattern and subjected to a curing treatment or the like, therebyforming a permanent pattern.

This permanent pattern formation is also applied to a package substrateinterposed between a semiconductor chip and a printed board. As for thepackage substrate, higher density packaging is recently demanded, andreduction in the wiring pitch, increase in the strength of a solderresist layer, enhancement of the insulating property, thin filmformation and the like are proceeding. In turn, resistance to repeatedcold/hot impacts (thermal cycle test resistance, TCT resistance) is morekeenly demanded. Also, reduction in the via diameter and in view ofmounting, a rectangular pattern profile are required.

Furthermore, the photosensitive composition for the formation of apermanent pattern represented by such a solder resist is demanded toensure that even when a member having a permanent pattern is placedunder high-temperature high-humidity conditions, deformation of thepermanent pattern or separation of the permanent pattern from the basematerial does not occur. For example, when such a defect is generated ina solder resist, there arises a problem that a wiring covered with thesolder resist develops a dendrite and adjacent wirings are electricallyconducted unintentionally. Therefore, it is also important that thesolder resist has excellent durability against high temperature and highhumidity.

On the other hand, a solid-state imaging device (image sensor) used incellular phones, digital cameras, digital videos, monitoring cameras andthe like is a photoelectric conversion device having an integratedcircuit formed using the production technique of a semiconductor device.In recent years, with reduction in size and weight of a cellular phoneor a digital camera, the solid-state imaging device is required to bemore downsized.

For downsizing the solid-state imaging device, a technique of applying athrough-electrode or thinning a silicon wafer has been proposed (see,for example, JP-A-2009-194396 (the term “JP-A” as used herein means an“unexamined published Japanese patent application”)). Downsizing can berealized by polishing and thereby thinning the silicon wafer, but due tothinning of the silicon wafer, light at a wavelength of 800 nm or moreis liable to be transmitted, though the effect of blocking light at 800nm or less is maintained. A photodiode used in the solid-state imagingdevice reacts also to light at a wavelength of 800 to 1,200 nm, andtransparency to light at a wavelength of 800 nm or more is found tocause a new problem that the pictorial quality is deteriorated.

The solid-state imaging device has a configuration that a color filterand a lens are provided adjacently to one side of a photodiode, aninfrared cut filter is present in the vicinity of the color filter orlens to cut light at a wavelength of 800 to 1,200 nm, and a metalwiring, a solder resist and the like are present on the opposite side ofthe color filter. For example, the space between metal wirings is filledwith a solder resist in many cases, but there is a problem that infraredlight such as leakage light intruding into the inside of a cellularphone, a digital camera or the like cannot be cut by the solder resist.To cope with this problem, a technique of further providing aninfrared-blocking layer on the outer side of the solder resist poor inthe light-blocking effect for infrared light and thereby ensuring theinfrared-blocking effect has been conventionally employed. However, aheight difference due to wiring or the like is generally present on thesolder resist and an infrared-blocking layer material can be hardlycoated to a uniform thickness on a substrate surface having a heightdifference, which gives rise to a problem that if a thin portion exits,light is transmitted therethrough.

In order to provide an infrared-blocking layer only in a desiredportion, the composition preferably exhibits photosensitivity and has aphotolithography performance enabling patterning by exposure. Thelight-blocking photosensitive composition having a photolithographyperformance includes a black resist using carbon black employed for theformation of an LCD color filter. The carbon black has a highlight-blocking effect in the visible region but exhibits a lowlight-blocking effect in the infrared region and when it is attempted toapply such a black resist as a solder resist, if carbon black is addedin an amount large enough to ensure the required light-blocking effectin the infrared region, this causes a problem that the light-blockingeffect in the visible region becomes excessively high, light at ashorter wavelength than the visible region, which is usually employedfor image formation and used at the exposure to high-pressure mercurylamp, KrF, ArF or the like, is also cut to incur reduction in thesensitivity, making it impossible to obtain sufficient photo-curability,and an excellent pattern cannot be obtained even through a developmentstep using an alkali developer.

Also, at present, an infrared-blocking layer is separately providedafter forming a solder resist by a coating method and therefore, in thesolder resist formation and the infrared-blocking layer formation, stepssuch as coating, exposure, development and post-heating must beperformed a plurality of times, which leads to a cumbersome process anda rise in the cost. In this regard, improvements are required.

For meeting the requirement, it has been attempted to impart alight-blocking effect to the solder resist itself, and, for example, ablack solder resist composition containing a black colorant, a colorantother than black, and a polyfunctional epoxy compound has been proposed(see, for example, JP-A-2008-257045). However, this composition ischaracterized in that the content of the black colorant is kept low byusing a colorant other than black in combination, and is practicallyinsufficient from the standpoint of satisfying both light-blockingeffect, particularly light-blocking effect in the infrared region, andpattern formability.

SUMMARY OF THE INVENTION

For the purpose of detecting the position of a semiconductor substrateby a visible light sensor in the process of producing a solid-stateimaging device, an alignment mark in a protruded form is often providedat the predetermined position on the surface on the metal wiring andsolder resist side (that is, the surface opposite the color filter orlens) of a semiconductor substrate of a solid-state imaging device.

In the case of the above-described configuration where aninfrared-blocking layer is further provided on the outer side of thesolder resist lacking the light-blocking effect for infrared light, itis considered that even when the infrared-blocking layer is a layerhaving a light-blocking effect also for visible light, the thickness ofthis layer need not be so large for the infrared-blocking purpose(because the infrared-blocking purpose can be achieved by a thinner filmthan the solder resist layer) and therefore, the detection by a visiblelight sensor does not face a serious trouble due to covering of thealignment mark with the infrared-blocking layer. However, particularlyin the configuration where, as in JP-A-2008-257045, a black colorant iscontained in the solder resist composition for imparting alight-blocking effect to the solder resist itself, when the alignmentmark is covered with a solder resist layer, maybe due to the thicknessof the solder resist layer, a trouble that the alignment mark is notdetected by the visible light sensor is liable to more often occur.

Under these circumstances, a polymerizable composition ensuringexcellent durability against high temperature and high humidity, highlight-blocking effect in the infrared region, high light transparency inthe visible region, and capability of forming an excellent pattern byalkali development is demanded at present. Above all, a polymerizablecomposition enabling realization of an excellent rectangular patternindependently of the material or the like of the substrate surface onwhich a pattern is provided, is keenly demanded.

Incidentally, JP-A-2009-205029 discloses a technique of using aninorganic near infrared absorber-containing layer as a nearinfrared-absorbing layer for an image display device, and, for example,a coating solution for near infrared-absorbing layer formation,containing a polymerizable compound, a polymerization initiator and anear infrared absorber, is described in working examples, but the layerobtained from this coating solution is not subjected to patternformation through exposure and alkali development. Actually, this layeris, even in the unexposed region, insufficient in solubility for analkali developer and has substantially no alkali developability.

The present invention has been made under these circumstances, and thetask of the present invention is to solve those various conventionalproblems and attain the following objects.

That is, an object of the present invention is to provide apolymerizable composition exhibiting high light-blocking effect in theinfrared region and high light transparency in the visible region andbeing capable of forming a pattern having a rectangular cross-sectionalshape as well as excellent durability (for example, durability againsthigh temperature/high humidity, or adherence to substrate) by alkalidevelopment, and a photosensitive layer, a permanent pattern, awafer-level lens, a solid-state imaging device and a pattern formingmethod each using the composition.

Another object of the present invention is to provide a polymerizablecomposition capable of suppressing development scum in the patternformation on a copper surface, and a photosensitive layer, a permanentpattern, a wafer-level lens, a solid-state imaging device and a patternforming method each using the composition.

The present invention has the following configurations, and theabove-described objects can be attained by these configurations.

(1) A polymerizable composition comprising:

(A) a polymerization initiator that is an acetophenone-based compound oran acylphosphine oxide-based compound,

(B) a polymerizable compound,

(C) at least either a tungsten compound or a metal boride, and

(D) an alkali-soluble binder.

(2) The polymerizable composition as described in (1) above, whichfurther comprises at least one compound selected from the groupconsisting of a thioxanthone-based compound, an acridone-based compoundand a coumarin-based compound.

(3) The polymerizable composition as described in (1) or (2) above,wherein the alkali-soluble binder has an acid group.

(4) The polymerizable composition as described in any one of (1) to (3)above, wherein the alkali-soluble binder has a crosslinking group.

(5) The polymerizable composition as described in any one of (1) to (4)above, wherein the alkali-soluble binder is a (meth)acrylic resin or aurethane-based resin.

(6) The polymerizable composition as described in (5) above, wherein thealkali-soluble binder is a urethane-based resin.

(7) The polymerizable composition as described in any one of (1) to (6)above, wherein the polymerizable composition contains a tungstencompound and the tungsten compound is represented by the followingformula (I):M_(x)W_(y)O_(z)  (I)

-   -   wherein M represents a metal, W represents tungsten, O        represents oxygen,        0.001≦x/y≦1.1, and        2.2≦z/y≦3.0.        (8) The polymerizable composition as described in (7) above,        wherein M is an alkali metal.        (9) The polymerizable composition as described in any one of (1)        to (8) above, wherein the polymerizable composition contains a        metal boride and the metal boride is at least one member        selected from the group consisting of lanthanum boride,        praseodymium boride, neodymium boride, cerium boride, yttrium        boride, titanium boride, zirconium boride, hafnium boride,        vanadium boride, tantalum boride, chromium boride, molybdenum        boride and tungsten boride.        (10) The polymerizable composition as described in (9) above,        wherein the metal boride is lanthanum boride.        (11) The polymerizable composition as described in any one        of (1) to (10) above, wherein the polymerizable compound is a        polyfunctional polymerizable compound having a plurality of        polymerizable groups within the molecule.        (12) The polymerizable composition as described in any one        of (1) to (11) above, which further comprises a filler.        (13) The polymerizable composition as described in any one        of (1) to (12) above, which is used for a solder resist.        (14) The polymerizable composition as described in (13) above,        wherein the solid content concentration is from 30 to 80 mass %        and the viscosity at 25° C. is from 10 to 3,000 mPa·s.        (15) A photosensitive layer formed of the polymerizable        composition described in any one of (1) to (14) above.        (16) A permanent pattern formed using the polymerizable        composition described in any one of (1) to (14) above.        (17) The permanent pattern as described in (16) above, wherein        the permanent pattern is a solder resist layer.        (18) The permanent pattern as described in (16) above, wherein        the permanent pattern is an infrared-blocking film.        (19) A wafer-level lens having a lens and the permanent pattern        described in (18) above formed in the circumferential edge part        of the lens.        (20) A solid-state imaging device having the permanent pattern        described in any one of (16) to (18) above.        (21) A solid-state imaging device comprising:

a solid-state imaging device substrate having formed on one surfacethereof an imaging element part, and

an infrared-blocking film provided on the other surface side of thesolid-state imaging device substrate,

wherein the infrared-blocking film is the permanent pattern described in(18) above.

(22) A pattern forming method comprising, in order, a step of formingthe photosensitive layer described in (15) above, a step ofpattern-exposing the photosensitive layer to cure the exposed area, anda step of removing the unexposed area by alkali development to form apermanent pattern.

According to the present invention, a polymerizable compositionexhibiting high light-blocking effect in the infrared region and highlight transparency in the visible region and being capable of forming apattern having a rectangular cross-sectional shape as well as excellentdurability (for example, durability against high temperature/highhumidity, or adherence to substrate) by alkali development, and aphotosensitive layer, a permanent pattern, a wafer-level lens, asolid-state imaging device and a pattern forming method each using thecomposition, can be provided.

Furthermore, according to the present invention, a polymerizablecomposition capable of suppressing development scum in the patternformation on a copper surface, and a photosensitive layer, a permanentpattern, a wafer-level lens, a solid-state imaging device and a patternforming method each using the composition, can be provided.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic cross-sectional view showing the configuration ofa camera module equipped with the solid-state imaging device accordingto an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view showing the solid-stateimaging device according to an embodiment of the present invention.

FIG. 3 is a plan view showing one example of the wafer-level lens array.

FIG. 4 is a cross-sectional view along line A-A in FIG. 3.

FIG. 5 is a view showing how a molding material working out to a lens issupplied to a substrate.

FIGS. 6A to 6C are views showing the procedure of molding a lens on asubstrate by using a mold.

FIGS. 7A to 7C are schematic views showing the process of forming apatterned light-blocking film on a substrate having molded thereon alens.

FIG. 8 is a cross-sectional view showing one example of the wafer-levellens array.

FIGS. 9A to 9C are schematic views showing another embodiment of theprocess of forming a light-blocking film.

FIGS. 10A to 10C are schematic views showing the process of molding alens on a substrate having thereon a patterned light-blocking film.

DESCRIPTION OF REFERENCE NUMERALS AND SIGNS

-   10 Silicon substrate-   12 Imaging device-   13 Interlayer insulating film-   14 Base layer-   15 Color filter-   16 Overcoat-   17 Microlens-   18 Light-blocking film-   20 Adhesive-   22 Insulating film-   23 Metal electrode-   24 Solder resist layer-   26 Internal electrode-   27 Device surface electrode-   30 Glass substrate-   40 Imaging lens-   41 Adhesive-   42 Infrared cut filter-   43 Adhesive-   44 Light-blocking and electromagnetic shield-   45 Adhesive-   50 Lens holder-   60 Solder ball-   70 Circuit substrate-   100 Solid-state imaging device substrate-   200 Camera module-   410 Substrate-   412, 420 Lens-   412 a Lens surface-   412 b Lens edge-   414 Light-blocking film-   414A Light-blocking coating layer-   414 a Lens opening-   450 Dispenser-   460, 480 Mold-   462, 482 Concave-   470 Mask

DETAILED DESCRIPTION OF THE INVENTION

The polymerizable composition of the present invention is described indetail below.

In the description of the present invention, when a group (atomic group)is denoted without specifying whether substituted or unsubstituted, thegroup includes both a group having no substituent and a group having asubstituent. For example, “an alkyl group” includes not only an alkylgroup having no substituent (unsubstituted alkyl group) but also analkyl group having a substituent (substituted alkyl group). Also, in thedescription of the present invention, the viscosity value indicates thevalue at 25° C.

The polymerizable composition of the present invention contains (A) apolymerization initiator that is an acetophenone-based compound or anacylphosphine oxide-based compound, (B) a polymerizable compound, (C) atleast either a tungsten compound or a metal boride, and (D) analkali-soluble binder, and, if desired, may contain an infrared-blockingmaterial other than the compound (C), a dispersant, a sensitizer, acrosslinking agent, a curing accelerator, a filler, an elastomer, asurfactant and other components.

The polymerizable composition of the present invention is, for example,a negative composition and is typically a negative resist composition.The configuration of this composition is described below.

[1] (A) Polymerization initiator that is an acetophenone-based compoundor an acylphosphine oxide-based compound

The polymerization initiator used in the polymerizable composition ofthe present invention is an acetophenone-based compound or anacylphosphine oxide-based compound, and this is a compound having anability of initiating polymerization of the polymerizable compound bylight but is preferably a photopolymerizable compound. In the case ofinitiating the polymerization by light, a compound havingphotosensitivity to light in the region from ultraviolet to visible ispreferred.

Examples of the polymerization initiator suitable for the presentinvention are described below, but the present invention is not limitedthereto.

Specific examples of the acetophenone-based compound include2,2-diethoxyacetophenone, p-dimethylaminoacetophenone,2-hydroxy-2-methyl-1-phenyl-propan-1-one, p-dimethylaminoacetophenone,4′-isopropyl-2-hydroxy-2-methyl-propiophenone,1-hydroxy-cyclohexyl-phenyl-ketone,2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one,2-tolyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one,2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one,2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one,2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one,2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone,and 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one.

Among these, an α-aminoacetophenone-based compound is preferred, and2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one is morepreferred.

Commercial products of the α-aminoacetophenone-based compound include,for example, IRGACURE 907, IRGACURE 369 and IRGACURE 379 (trade names,all produced by BASF Japan).

Specific examples of the acylphosphine oxide-based compound include2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide andbis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide.

Usable commercial products of the acylphosphine oxide-based compoundinclude, for example, IRGACURE-819, Lucirin TPO, Lucirin TPO-L andDAROCURE-TPO (trade names, all produced by BASF Japan).

One kind of a polymerization initiator may be used alone, or two or morekinds of polymerization initiators may be used in combination.

The content of the polymerization initiator is preferably from 0.01 to30 mass %, more preferably from 0.1 to 20 mass %, still more preferablyfrom 0.1 to 15 mass %, based on the entire solid content by mass of thepolymerizable composition of the present invention.

[2] (B) Polymerizable Compound

The polymerizable composition of the present invention contains apolymerizable compound. The polymerizable compound used here may be anycompound as long as it is a compound having, in the molecule, afunctional group capable of undergoing a reaction by the effect of atleast one of an acid, a radical and heat (in the description of thepresent invention, such a functional group is sometimes referred to as a“polymerizable group”), and a polyfunctional polymerizable compoundhaving a plurality of polymerizable groups in the molecule is preferred.

Example of the polymerizable compound having a polymerizable functionalgroup capable of reacting to at least one of an acid, a radical and heatinclude an ethylenically unsaturated group-containing compound having anethylenically unsaturated group such as unsaturated ester functionalgroup, unsaturated amide group, vinyl ether group and allyl group; amethylol compound; a bismaleimide compound; a benzocyclobutene compound,a bisallylnadiimide compound; and a benzoxazine compound.

The polymerizable compound that can be preferably used in the presentinvention includes a general radical polymerizable compound, andcompounds widely known as the compound having an ethylenicallyunsaturated double bond in this industrial field can be used without anyparticular limitation.

These compounds have a chemical form of, for example, a monomer, aprepolymer (that is, dimer, trimer or oligomer), or a mixture orcopolymer thereof.

Examples of the monomer and a copolymer thereof include an unsaturatedcarboxylic acid (such as acrylic acid, methacrylic acid, itaconic acid,crotonic acid, isocrotonic acid and maleic acid), its esters and amides,and a copolymer thereof. Preferably, an unsaturated carboxylic acidester, an ester of an unsaturated carboxylic acid and an aliphaticpolyhydric alcohol compound, and amides of an unsaturated carboxylicacid and an aliphatic polyvalent amino compound, are used.

Particularly, an ester of an unsaturated carboxylic acid and analiphatic polyhydric alcohol compound can develop high hydrophobicity inthe exposed area and is preferred because a pattern having a desiredprofile can be easily formed by alkali development and also, a patternhaving high durability is obtained (in particular, when higherdurability is required of the solder resist, for example, when thewiring density of the metal wiring covered with a solder resist is high,the above-described effects are prominent).

In addition, for example, an addition reaction product of unsaturatedcarboxylic acid esters or amides having a nucleophilic substituent suchas hydroxyl group, amino group and mercapto group to monofunctional orpolyfunctional isocyanates or epoxies, and a dehydration condensationreaction product with a monofunctional or polyfunctional carboxylicacid, are also suitably used.

An addition reaction product of unsaturated carboxylic acid esters oramides having an electrophilic substituent such as isocyanate group andepoxy group to monofunctional or polyfunctional alcohols, amines orthiols, and a substitution reaction product of unsaturated carboxylicacid esters or amides having a leaving substituent such as halogen groupand tosyloxy group with monofunctional or polyfunctional alcohols,amines or thiols, are also preferred. As another example, compoundswhere the above-described unsaturated carboxyl acid is replaced by anunsaturated phosphonic acid, a styrene or a vinyl ether, may be alsoused.

The unsaturated carboxylic acid ester is preferably a methacrylic acidester, and examples thereof include tetramethylene glycoldimethacrylate, triethylene glycol dimethacrylate, neopentyl glycoldimethacrylate, trimethylolpropane trimethacrylate, trimethylolethanetrimethacrylate, ethylene glycol dimethacrylate, 1,3-butanedioldimethacrylate, hexanediol dimethacrylate, pentaerythritoldimethacrylate, pentaerythritol trimethacrylate, pentaerythritoltetramethacrylate, dipentaerythritol dimethacrylate, dipentaerythritolhexamethacrylate, sorbitol trimethacrylate, sorbitol tetramethacrylate,bis[p-(3-methacryloxy-2-hydroxypropoxy)phenyl]dimethylmethane,bis-[p-(methacryloxyethoxy)phenyl]dimethylmethane, and their EO-modifiedor PO-modified products.

The unsaturated carboxylic acid ester is also preferably an itaconicacid ester, and examples thereof include ethylene glycol diitaconate,propylene glycol diitaconate, 1,3-butanediol diitaconate, 1,4-butanedioldiitaconate, tetramethylene glycol diitaconate, pentaerythritoldiitaconate, and sorbitol tetraitaconate. Examples of the crotonic acidester include ethylene glycol dicrotonate, tetramethylene glycoldicrotonate, pentaerythritol dicrotonate, and sorbitol tetradicrotonate.Examples of the isocrotonic acid ester include ethylene glycoldiisocrotonate, pentaerythritol diisocrotonate, and sorbitoltetraisocrotonate. Examples of the maleic acid ester include ethyleneglycol dimaleate, triethylene glycol dimaleate, pentaerythritoldimaleate, and sorbitol tetramaleate.

Specific examples of the ester monomer of an aliphatic polyhydricalcohol compound with an unsaturated carboxylic acid include, as the(meth)acrylic acid ester, ethylene glycol diacrylate, triethylene glycoldiacrylate, 1,3-butanediol diacrylate, tetramethylene glycol diacrylate,propylene glycol diacrylate, neopentyl glycol diacrylate,trimethyloipropane triacrylate, trimethylolpropanetri(acryloyloxypropyl)ether, trimethylolethane triacrylate, hexanedioldiacrylate, 1,4-cyclohexanediol diacrylate, tetraethylene glycoldiacrylate, tricyclodecanedimethanol diacrylate,tricyclodecanedimethanol dimethacrylate, pentaerythritol diacrylate,pentaerythritol triacrylate, pentaerythritol tetraacrylate,dipentaerythritol diacrylate, dipentaerythritol hexaacrylate, sorbitoltriacrylate, sorbitol tetraacrylate, sorbitol pentaacrylate, sorbitolhexaacrylate, tri(acryloyloxyethyl) isocyanurate, polyester acrylateoligomer, and EO-modified or PO-modified products of these compounds.

Other preferred examples of the ester include aliphatic alcohol estersdescribed in JP-B-51-47334 and JP-A-57-196231, those having an aromaticframework described in JP-A-59-5240, JP-A-59-5241 and JP-A-2-226149, andthose having an amino group described in JP-A-1-165613. These estermonomers may be used also as a mixture.

Specific examples of the amide monomer of an aliphatic polyvalent aminecompound with an unsaturated carboxylic acid includemethylenebis-acrylamide, methylenebis-methacrylamide,1,6-hexamethylenebis-acrylamide, 1,6-hexamethylenebis-methacrylamide,diethylenetriaminetrisacrylamide, xylylenebisacrylamide, andxylylenebismethacrylamide. Other preferred examples of the amide-basedmonomer include those having a cyclohexylene structure described inJP-B-54-21726.

An addition-polymerizable urethane-based compound produced by anaddition reaction of an isocyanate to a hydroxyl group is alsopreferred, and specific examples thereof include a vinyl urethanecompound having two or more polymerizable vinyl groups per moleculeobtained by adding a hydroxyl group-containing vinyl monomer representedby the following formula (E) to a polyisocyanate compound having two ormore isocyanate groups per molecule described in JP-B-48-41708.CH₂═C(R⁴)COOCH₂CH(R⁵)OH  (E)[wherein each of R⁴ and R⁵ independently represents H or CH₃].

Furthermore, urethane acrylates described in JP-A-51-37193, JP-B-2-32293and JP-B-2-16765 and urethane compounds having an ethylene oxide-basedframework described in JP-B-58-49860, JP-B-56-17654, JP-B-62-39417 andJP-B-62-39418 are also preferred. In addition, whenaddition-polymerizable compounds having an amino structure or sulfidestructure in the molecule described in JP-A-63-277653, JP-A-63-260909and JP-A-1-105238 are used, a photopolymerizable composition veryexcellent in the photosensitivity can be obtained.

Other examples include a polyfunctional acrylate or methacrylate such aspolyester acrylates described in JP-A-48-64183, JP-B-49-43191 andJP-B-52-30490, and epoxy acrylates obtained by reacting an epoxy resinwith a (meth)acrylic acid. Other examples also include specificunsaturated compounds described in JP-B-46-43946, JP-B-1-40337 andJP-B-1-40336, and vinylphosphonic acid-based compounds described inJP-A-2-25493. In some cases, a perfluoroalkyl group-containing structuredescribed in JP-A-61-22048 is suitably used. Furthermore, thoseintroduced as photocurable monomers and oligomers in Journal of TheAdhesion Society of Japan, Vol. 20, No. 7, pp. 300-308 (1984) may bealso used.

In the present invention, when a radical polymerizable compound isadded, in view of curing sensitivity, a polyfunctional polymerizablecompound containing two or more ethylenically unsaturated bonds ispreferably used, and it is more preferred to contain three or moreethylenically unsaturated bond. Above all, the compound preferablycontains two or more, more preferably three or more, most preferablyfour or more, (meth)acrylic acid ester structures.

Furthermore, in view of curing sensitivity and developability of theunexposed area, a compound containing an EO-modified product ispreferred, and in view of curing sensitivity and strength of the exposedarea, a compound containing a urethane bond is preferably used. Inaddition, in view of developability at the pattern formation, a compoundhaving an acid group is preferably used.

From these viewpoints, preferred examples of the polymerizable compoundfor use in the present invention include bisphenol A diacrylate.EO-modified bisphenol A diacrylate, trimethylolpropane triacrylate,trimethylolpropane tri(acryloyloxypropyl)ether, trimethylolethanetriacrylate, tetraethylene glycol diacrylate, pentaerythritoldiacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate,dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate,dipentaerythritol hexaacrylate, sorbitol triacrylate, sorbitoltetraacrylate, sorbitol pentaacrylate, sorbitol hexaacrylate,tri(acryloyloxyethyl) isocyanurate, EO-modified pentaerythritoltetraacrylate, and EO-modified dipentaerythritol hexaacrylate. Also, asthe commercially available product, urethane oligomer UAS-10, UAB-140(both produced by Sanyo Kokusaku Pulp Co., Ltd.), DPHA-40H (produced byNippon Kayaku Co., Ltd.), UA-306H, UA-306T, UA-306I, AH-600, T-600 andAI-600 (all produced by Kyoeisha Chemical Co., Ltd.) are preferred.

Among these, EO-modified bisphenol A diacrylate, pentaerythritoltriacrylate, pentaerythritol tetraacrylate, dipentaerythritolpentaacrylate, dipentaerythritol hexaacrylate, tri(acryloyloxyethyl)isocyanurate, EO-modified pentaerythritol tetraacrylate, and EO-modifieddipentaerythritol hexaacrylate are more preferred, and as thecommercially available product, DPHA-40H (produced by Nippon Kayaku Co.,Ltd.), UA-306H, UA-306T, UA-306I, AH-600, T-600 and AI-600 (produced byKyoeisha Chemical Co., Ltd.) are more preferred.

Ethylenically unsaturated compounds having an acid group are alsopreferred, and examples of the commercially available product thereofinclude TO-756 that is a carboxyl group-containing trifunctionalacrylate produced by Toagosei CO., Ltd., and TO-1382 that is a carboxylgroup-containing pentafunctional acrylate.

In addition, examples of the highly heat-resistant polymerizablecompound include benzocyclobutene (BCB), bisallylnadiimide (BANI),benzoxazine, melamine and their analogues.

The content of the polymerizable compound is preferably from 3 to 80mass %, more preferably from 5 to 50 mass %, based on the entire solidcontent by mass of the polymerizable composition of the presentinvention.

As the polymerizable compound, two or more kinds of compounds can beused.

[3] (C) at Least Either a Tungsten Compound or a Metal Boride

The polymerizable composition of the present invention contains (C) atleast either a tungsten compound or a metal boride (hereinafter,sometimes collectively referred to as a “compound (C)”).

The tungsten compound and the metal boride are an infrared-blockingmaterial having high absorption of infrared light (light at a wavelengthof about 800 to 1,200 nm) (that is, high light-blocking effect(shielding property) for infrared ray) and low absorption of visiblelight. Accordingly, by virtue of containing the compound (C), thepolymerizable composition of the present invention can form a patternhaving a high light-blocking effect in the infrared region and highlight transparency in the visible region.

Also, the tungsten compound and the metal boride exhibit a smallabsorption for light at a wavelength shorter than the visible region,which is employed in the image formation and used at exposure to ahigh-pressure mercury lamp, KrF, ArF or the like. Therefore, bycombining the compound (C) with the above-described specificpolymerization initiator, polymerizable compound and alkali-solublebinder, an excellent pattern is obtained and at the same time,development scum can be suppressed in the pattern formation on a coppersurface.

The tungsten compound includes, for example, a tungsten oxide-basedcompound, a tungsten boride-based compound and a tungsten sulfide-basedcompound and is preferably a tungsten oxide-based compound representedby the following formula (compositional formula) (I):M_(x)W_(y)O_(z)  (I)

-   -   wherein M represents a metal, W represents tungsten, O        represents oxygen,        0.001≦x/y≦1.1, and        2.2≦z/y≦3.0.

The metal of M includes an alkali metal, an alkaline earth metal, Mg,Zr, Cr, Mn, Fe, Ru, Co, Rh, Ir, Ni, Pd, Pt, Cu, Ag, Au, Zn, Cd, Al, Ga,In, Tl, Sn, Pb, Ti, Nb, V, Mo, Ta, Re, Be, Hf, Os and Bi and ispreferably an alkali metal. The metal of M may be one kind of a metal ortwo or more kinds of metals.

M is preferably an alkali metal, more preferably Rb or Cs, still morepreferably Cs.

When x/y is 0.001 or more, the infrared ray can be sufficiently blocked,and when it is 1.1 or less, production of an impurity phase in thetungsten compound can be more unfailingly avoided.

When z/y is 2.2 or more, chemical stability as the material can be moreenhanced, and when it is 3.0 or less, the infrared ray can besufficiently blocked.

Specific examples of the tungsten oxide-based compound represented byformula (I) include Cs_(0.33)WO₃, Rb_(0.33)WO₃, K_(0.33)WO₃ andBa_(0.33)WO₃. The compound is preferably Cs_(0.33)WO₃ or Rb_(0.33)WO₃,more preferably Cs_(0.33)WO₃.

The tungsten compound is preferably a fine particle. The averageparticle diameter of the tungsten fine particle is preferably 800 nm orless, more preferably 400 nm or less, still more preferably 200 nm orless. When the average particle diameter is in this range, the tungstenfine particle is scarcely allowed to block the visible light because oflight scattering, so that light transparency in the visible region canbe more successfully ensured. From the standpoint of avoiding lightscattering, the average particle diameter is preferably smaller, but forthe reason of easy handling or the like at the production, the averageparticle diameter of the tungsten fine particle is usually 1 nm or more.

As the tungsten compound, two or more kinds of compounds may be used.

The tungsten compound is available as a commercial product but when thetungsten compound is, for example, a tungsten oxide-based compound, thetungsten oxide-based compound can be obtained by a method ofheat-treating a tungsten compound in an inert gas atmosphere or areducing gas atmosphere (see, Japanese Patent 4,096,205).

The tungsten oxide-based compound is also available, for example, as atungsten fine particle dispersion such as YMF-02 produced by SumitomoMetal Industries, Ltd.

The metal boride may be one member or two or more members selected fromlanthanum boride (LaB₆), praseodymium boride (PrB₆), neodymium boride(NdB₆), cerium boride (CeB₆), yttrium boride (YB₆), titanium boride(TiB₂), zirconium boride (ZrB₂), hafnium boride (HfB₂), vanadium boride(VB₂), tantalum boride (TaB₂), chromium boride (CrB, CrB₂), molybdenumboride (MoB₂, MO₂B₅, MoB) and tungsten boride (W₂B₅), and is preferablylanthanum boride (LaB₆).

The metal boride is preferably a fine particle. The average particlediameter of the metal boride fine particle is preferably 800 nm or less,more preferably 300 nm or less, still more preferably 100 nm or less.When the average particle diameter is in this range, the metal boridefine particle is scarcely allowed to block the visible light because oflight scattering, so that light transparency in the visible region canbe more successfully ensured. From the standpoint of avoiding lightscattering, the average particle diameter is preferably smaller, but forthe reason of easy handling or the like at the production, the averageparticle diameter of the metal boride fine particle is usually 1 nm ormore.

Also, two or more kinds of metal borides may be used.

The metal boride is available as a commercial product and is availablealso as a metal boride fine particle dispersion such as KHF-7 producedby Sumitomo Metal Industries, Ltd.

The content of the compound (C) is preferably from 0.1 to 20 mass %,more preferably from 1 to 10 mass %, based on the entire solid contentby mass of the polymerizable composition of the present invention.

In the case where the polymerizable composition of the present inventioncontains a tungsten compound, the content of the tungsten compound ispreferably from 3 to 20 mass %, more preferably from 5 to 10 mass %,based on the entire solid content by mass of the polymerizablecomposition of the present invention.

In the case where the polymerizable composition of the present inventioncontains a metal boride, the content of the metal boride is preferablyfrom 0.1 to 10 mass %, more preferably from 1 to 5 mass %, based on theentire solid content by mass of the polymerizable composition of thepresent invention.

[4] (D) Alkali-Soluble Binder

The polymerizable composition of the present invention contains analkali-soluble binder (alkali-soluble resin). Thanks to this binder,when exposure is performed to form a pattern in the film obtained fromthe polymerizable composition, the unexposed area can be removed with analkali developer, and an excellent pattern can be formed by alkalidevelopment.

The alkali-soluble binder is not particularly limited as long as it isalkali-soluble, and an appropriate alkali-soluble binder may be selectedaccording to the purpose, but examples thereof include a (meth)acrylicresin, a urethane-based resin, polyvinyl alcohol, polyvinylbutyral,polyvinylformal, polyamide and polyester. The alkali-soluble binder ispreferably a (meth)acrylic resin or a urethane-based resin.

From the standpoint that the thermal cycle test resistance (TCTresistance) can be further enhanced, the alkali-soluble binder is morepreferably a urethane-based resin.

The alkali-soluble binder preferably has an acid group.

Examples of the acid group include a carboxylic acid group, a sulfonicacid group, a phosphonic acid group, a phosphoric acid group and asulfonamide group, and in view of availability of the raw material, acarboxylic acid group is preferred.

The alkali-soluble binder having an acid group is not particularlylimited but is preferably a polymer obtained by using, as a monomercomponent, an acid group-containing polymerizable compound and from thestandpoint of adjusting the acid value, a copolymer obtained bycopolymerizing an acid group-containing polymerizable compound and anacid group-free polymerizable compound is more preferred.

The acid group-containing polymerizable compound is not particularlylimited and may be appropriately selected according to the purpose, andexamples thereof include acrylic acid, methacrylic acid, itaconic acid,crotonic acid, isocrotonic acid, maleic acid, and p-carboxylstyrene,with acrylic acid, methacrylic acid and p-carboxylstyrene beingpreferred. One of these compounds may be used alone, or two or morethereof may be used in combination.

The acid group-free polymerizable compound is not particularly limited,but preferred examples thereof include a (meth)acrylic acid ester (suchas alkyl ester, aryl ester and aralkyl ester).

The alkyl group in the alkyl ester moiety of the (meth)acrylic acidester may be linear or branched and is preferably an alkyl group havinga carbon number of 1 to 10, more preferably an alkyl group having acarbon number of 1 to 6.

The aryl group in the aryl ester moiety of the (meth)acrylic acid esteris preferably an aryl group having a carbon number of 6 to 14, morepreferably an aryl group having a carbon number of 6 to 10.

The aralkyl group in the aralkyl ester moiety of the (meth)acrylic acidester is preferably an aralkyl group having a carbon number of 7 to 20,more preferably an aralkyl group having a carbon number of 7 to 12.

The molar ratio between a monomer corresponding to the acidgroup-containing polymerizable compound and a monomer corresponding tothe acid group-free polymerizable compound is usually from 1:99 to 99:1,preferably from 30:70 to 99:1, more preferably from 50:50 to 99:1.

The content of the acid group in the alkali-soluble binder is notparticularly limited but is preferably from 0.5 to 4.0 meq/g, morepreferably from 1.0 to 3.0 meq/g. When the content is 0.5 meq/g or more,satisfactory alkali developability is obtained and an excellent patterncan be more unfailingly obtained. Also, when the content is 4.0 meq/g orless, the fear of impairing the strength of the permanent pattern can bereliably avoided.

The alkali-soluble binder preferably further has a crosslinking group,and this is preferred particularly in that both the curability of theexposed area and alkali developability of the unexposed area can beenhanced and a pattern having high durability is obtained (inparticular, when higher durability is required of the solder resist, forexample, when the wiring density of the metal wiring covered with asolder resist is high, the above-described effects are prominent). Thecrosslinking group as used herein indicates a group capable ofcrosslinking the binder polymer in the process of polymerizationreaction brought about in the photosensitive layer when thephotosensitive layer obtained from the polymerizable composition isexposed or heated. The crosslinking group is not particularly limited aslong as it is a group having such a function, but examples of thefunctional group capable of undergoing an addition polymerizationreaction include an ethylenically unsaturated bond group, an amino groupand an epoxy group. The crosslinking group may be also a functionalgroup capable of becoming a radical upon irradiation with light, andexamples of such a crosslinking group include a thiol group and ahalogen group. Above all, an ethylenically unsaturated bond group ispreferred. The ethylenically unsaturated bond group is preferably astyryl group, a (meth)acryloyl group or an allyl group, and from thestandpoint of satisfying both the stability of the crosslinking groupbefore exposure and the strength of the permanent pattern, a(meth)acryloyl group is more preferred.

For example, a free radial (a polymerization initiating radical or aradical grown in the polymerization process of a polymerizable compound)is added to the crosslinking functional group of the alkali-solublebinder to cause addition polymerization between polymers directly orthrough a polymerization chain of the polymerizable compound, as aresult, crosslinking is formed between polymer molecules and curing isthereby effected. Alternatively, an atom (for example, a hydrogen atomon the carbon atom adjacent to the functional crosslinkable group) inthe polymer is withdrawn by a free radical to produce a polymer radical,and the polymer radicals combine with each other to form crosslinkingbetween polymer molecules, thereby effecting curing.

The content of the crosslinkable group in the alkali-soluble binder isnot particularly limited but is preferably from 0.5 to 3.0 meq/g, morepreferably from 1.0 to 3.0 meq/g, still more preferably from 1.5 to 2.8meq/g. When the content is 0.5 meq/g or more, the amount of curingreaction is sufficiently large and high sensitivity is obtained, andwhen 3.0 meq/g or less, storage stability of the polymerizablecomposition can be enhanced.

The content (meg/g) above can be measured, for example, by iodine valuetitration.

The alkali-soluble binder having a crosslinking group is described indetail in JP-A-2003-262958, and compounds described in this publicationcan be used also in the present invention.

The alkali-soluble binder having a crosslinking group is preferably analkali-soluble binder having an acid group and a crosslinking group, andrepresentative examples thereof are the followings:

(1) a urethane-modified polymerizable double bond-containing acrylicresin obtained by reacting a compound which has one unreacted isocyanategroup allowed to remain after previously reacting an isocyanate groupand an OH group and contains at least one (meth)acryloyl group, with acarboxyl group-containing acrylic resin;

(2) an unsaturated group-containing acrylic resin obtained by reacting acarboxyl group-containing acrylic resin with a compound having both anepoxy group and a polymerizable double bond within the molecule; and

(3) a polymerizable double bond-containing acrylic resin obtained byreacting an OH group-containing acrylic resin with a dibasic acidanhydride having a polymerizable double bond.

Among these, the resins of (1) and (2) are preferred.

The alkali-soluble binder having an acid group and a crosslinking groupalso includes, for example, a polymer compound having an acidic groupand an ethylenically unsaturated bond in the side chain and having abisphenol A-type framework and a bisphenol F-type framework, a novolakresin having an acidic group and an ethylenically unsaturated bond, anda resol resin. These resins can be obtained by the technique describedin paragraphs [0008] to [0027] of JP-A-11-240930.

As described above, the alkali-soluble binder is preferably a(meth)acrylic resin or a urethane-based resin, and the “(meth)acrylicresin” is preferably a copolymer having, as a polymerization component,a (meth)acrylic acid derivative such as (meth)acrylic acid,(meth)acrylic acid ester (e.g., alkyl ester, aryl eater, aralkyl ester),(meth)acrylamide and (meth)acrylamide derivative. The “urethane-basedresin” is preferably a polymer produced by a condensation reactionbetween a compound having two or more isocyanate groups and a compoundhaving two or more hydroxyl groups.

The (meth)acrylic resin is preferably, for example, a copolymer havingan acid group-containing repeating unit. Preferred examples of the acidgroup include those described above. As the acid group-containingrepeating unit, a (meth)acrylic acid-derived repeating unit or arepeating unit represented by the following formula (I) is preferablyused.

(In formula (I), R¹ represents a hydrogen atom or a methyl group, R²represents a single bond or an n+1-valent linking group, A represents anoxygen atom or —NR³—, R³ represents a hydrogen atom or a monovalenthydrocarbon group having a carbon number of 1 to 10, and n represents aninteger of 1 to 5.)

The linking group represented by R² in formula (I) is preferablycomposed of one or more atoms selected from the group consisting of ahydrogen atom, a carbon atom, an oxygen atom, a nitrogen atom, a sulfuratom and a halogen atom, and the number of atoms constituting thelinking groups represented by R² is preferably from 1 to 80. Specificexamples of the linking group include an alkylene group and an arylenegroup, and the linking group may have a structure where a plurality ofdivalent linking groups described above are connected through any one ofan amide bond, an ether bond, a urethane bond, a urea bond and an esterbond. R² is preferably a single bond, an alkylene group, or a structurewhere a plurality of alkylene groups are connected through at least oneof an amide bond, an ether bond, a urethane bond, a urea bond and anester bond.

The carbon number of the alkylene group is preferably from 1 to 5, morepreferably from 1 to 3.

The carbon number of the arylene group is preferably from 6 to 14, morepreferably from 6 to 10.

The alkylene group and arylene group may further have a substituent, andexamples of the substituent include a monovalent nonmetallic atom groupexcluding hydrogen atom and include a halogen atom (—F, —Br, —Cl, —I), ahydroxyl group, a cyano group, an alkoxy group, an aryloxy group, amercapto group, an alkylthio group, an arylthio group, an alkylcarbonylgroup, an arylcarbonyl group, a carboxyl group and its conjugate basegroup, an alkoxycarbonyl group, an aryloxycarbonyl group, a carbamoylgroup, an aryl group, an alkenyl group, and an alkynyl group.

The hydrocarbon group of R³ preferably has a carbon number of 1 to 10,more preferably from 1 to 5, still more preferably from 1 to 3.

R³ is most preferably a hydrogen atom or a methyl group.

n is preferably 1 to 3, more preferably 1 or 2, and most preferably 1.

The ratio (mol %) of the acid group-containing repeating unit occupyingin all repeating unit components of the (meth)acrylic resin is, in viewof developability, preferably from 10 to 90%, and in view of satisfyingboth developability and strength of the permanent pattern, the ratio ismore preferably from 50 to 85%, still more preferably from 60 to 80%.

As already stated, the (meth)acrylic resin preferably further has acrosslinking group, and specific examples and content of thecrosslinking group are the same as those described above.

The (meth)acrylic polymer for use in the present invention may contain,in addition to the acid group-containing polymerization unit and thecrosslinking group-containing polymerization unit, a polymerization unitof (meth)acrylamide or a derivative thereof, a polymerization unit ofα-hydroxymethyl acrylate, and a polymerization unit of styrenederivative. The alkyl group of the (meth)acrylic acid alkyl ester ispreferably an alkyl group having a carbon number of 1 to 5 or an alkylgroup with the above-described substituent having a carbon number of 2to 8, more preferably a methyl group. Examples of the (meth)acrylic acidaralkyl ester include benzyl (meth)acrylate. Examples of the(meth)acrylamide derivative include N-isopropylacrylamide,N-phenylmethacrylamide, N-(4-methoxycarbonylphenyl)methacrylamide,N,N-dimethylacrylamide, and morpholinoacrylamide. Examples of theα-hydroxymethyl acrylate include ethyl α-hydroxymethylacrylate andcyclohexyl α-hydroxymethylacrylate. Examples of the styrene derivativeinclude styrene and 4-tert-butylstyrene.

The “urethane-based resin” is preferably a urethane-based resin having,as a basic framework, a structural unit that is a reaction product of atleast one diisocyanate compound represented by the following formula (1)and at least one diol compound represented by formula (2).OCN—X—NCO  (1)HO-L¹-OH  (2)

In formulae (1) and (2), each of X and L¹ independently represents adivalent organic residue.

At least one of the diisocyanate compound represented by formula (2)preferably contains an acid group. In this case, an alkali-solubleurethane-based resin having introduced thereinto an acid group can besuitably produced as a reaction product of the diisocyanate compound andthe diol compound. According to such a method, an alkali-solubleurethane-based resin can be more easily produced than in the case ofsubstituting or introducing an acid group on/into a desired side chainafter the reaction and production of a urethane-based resin.

Out of at least either the diisocyanate compound represented by formula(1) or the diol compound represented by formula (2), at least onecompound preferably has a crosslinking group. Examples of thecrosslinking group include those described above. By containing acrosslinking group, an alkali-soluble urethane-based resin havingintroduced thereinto a crosslinking group can be suitably produced as areaction product of the diisocyanate compound and the diol compound.According to such a method, a urethane-based resin having a crosslinkinggroup can be more easily produced than in the case of substituting orintroducing a crosslinking group on/into a desired side chain after thereaction and production of a urethane-based resin.

(1) Diisocyanate Compound

In formula (1), X is preferably a divalent aliphatic group, an aromatichydrocarbon group, or a mixture thereof, and the carbon number thereofis preferably from 1 to 20, more preferably from 1 to 15. The divalentaliphatic or aromatic hydrocarbon group may further have a substituentincapable of reacting with the isocyanate group.

Specific examples of the diisocyanate compound represented by formula(1) include the followings:

that is, an aromatic diisocyanate compound such as 2,4-tolylenediisocyanate, dimerized 2,4-tolylene diisocyanate, 2,6-tolylenediisocyanate, p-xylylene diisocyanate, m-xylylene diisocyanate,4,4′-diphenylmethane diisocyanate, 1,5-naphthylene diisocyanate, and3,3′-dimethylbiphenyl-4,4′-diisocyanate; an aliphatic diisocyanatecompound such as hexamethylene diisocyanate, trimethylhexamethylenediisocyanate, lysine diisocyanate, and dimer acid diisocyanate; analicyclic diisocyanate compound such as isophorone diisocyanate,4,4′-methylenebis(cyclohexylisocyanate), methylcyclohexane-2,4(or2,6)-diisocyanate, and 1,3-(isocyanatomethyl)cyclohexane; and adiisocyanate compound that is a reaction product of a diol with adiisocyanate, such as adduct of 1 mol of 1,3-butylene glycol and 2 molof tolylene diisocyanate.

In the case where the diisocyanate compound represented by formula (1)has a crosslinking group, the diisocyanate compound includes, forexample, a product obtained by an addition reaction of a triisocyanatecompound with 1 equivalent of a monofunctional alcohol having acrosslinking group (e.g., ethylene unsaturated bond group) or amonofunctional amine compound. Specific examples of the triisocyanatecompound, the crosslinking group-containing monofunctional alcohol, andthe monofunctional amine compound include, but are not limited to, thosedescribed in paragraphs [0034], [0035] and [0037] to [0040] of JapanesePatent 4,401,262.

Specific examples of the crosslinking group-containing diisocyanatecompound include, but are not limited to, those described in paragraphs[0042] to [0049] of Japanese Patent 4,401,262.

(2) Dial Compound

The diol compound represented by formula (2) widely includes, forexample, a polyether diol compounds, a polyester diol compound, and apolycarbonate diol compound. The polyether diol compound includescompounds represented by the following formulae (3), (4), (5), (6) and(7), and a random copolymer of hydroxyl group-terminated ethylene oxideand propylene oxide.

In formulae (3) to (7), R¹⁴ represents a hydrogen atom or a methylgroup, and X¹ represents a group shown below. Each of a, b, c, d, e, f,and g represents an integer of 2 or more and is preferably an integer of2 to 100. Two d's may be the same or different. Also, two X¹s may be thesame or different.

Specific examples of the polyether diol compounds represented byformulae (3) and (4) include the followings: that is, diethylene glycol,triethylene glycol, tetraethylene glycol, pentaethylene glycol,hexaethylene glycol, heptaethylene glycol, octaethylene glycol,di-1,2-propylene glycol, tri-1,2-propylene glycol, tetra-1,2-propyleneglycol, hexa-1,2-propylene glycol, di-1,3-propylene glycol,tri-1,3-propylene glycol, tetra-1,3-propylene glycol, di-1,3-butyleneglycol, tri-1,3-butylene glycol, hexa-1,3-butylene glycol, polyethyleneglycol having a weight average molecular weight of 1,000, polyethyleneglycol having a weight average molecular weight of 1,500, polyethyleneglycol having a weight average molecular weight of 2,000, polyethyleneglycol having a weight average molecular weight of 3,000, polyethyleneglycol having a weight average molecular weight of 7,500, polypropyleneglycol having a weight average molecular weight of 400, polypropyleneglycol having a weight average molecular weight of 700, polypropyleneglycol having a weight average molecular weight of 1,000, polypropyleneglycol having a weight average molecular weight of 2,000, polypropyleneglycol having a weight average molecular weight of 3,000, andpolypropylene glycol having a weight average molecular weight of 4,000.

Specific examples of the polyether diol compound represented by formula(5) include the followings: that is, PTMG650, PTMG1000, PTMG2000 andPTMG3000 (trade names) produced by Sanyo Chemical Industries, Ltd.

Specific examples of the polyether diol compound represented by formula(6)

include the followings: that is, NEWPOL PE-61, NEWPOL PE-62, NEWPOLPE-64, NEWPOL PE-68, NEWPOL PE-71, NEWPOL PE-74, NEWPOL PE-75, NEWPOLPE-78, NEWPOL PE-108, NEWPOL PE-128 and NEWPOL PE-61 (trade names)produced by Sanyo Chemical Industries, Ltd.

Specific examples of the polyether diol compound represented by formula(7) include the followings: that is, NEWPOL BPE-20, NEWPOL BPE-20F,NEWPOL BPE-20NK, NEWPOL BPE-20T, NEWPOL BPE-20G, NEWPOL BPE-40, NEWPOLBPE-60, NEWPOL BPE-100, NEWPOL BPE-180, NEWPOL BPE-2P, NEWPOL BPE-23P,NEWPOL BPE-3P and NEWPOL BPE-5P (trade names) produced by Sanyo ChemicalIndustries, Ltd.

Specific examples of the random copolymer of hydroxyl group-terminatedethylene oxide and propylene oxide include the followings:

that is, NEWPOL 50HB-100, NEWPOL 50HB-260, NEWPOL 50HB-400, NEWPOL50HB-660, NEWPOL 50HB-2000 and NEWPOL 50HB-5100 (trade names) producedby Sanyo Chemical Industries, Ltd.

The polyester diol compound includes compounds represented by formulae(8) and (9):

In formulae (8) and (9), each of L², L³ and L⁴ represents a divalentaliphatic or aromatic hydrocarbon group, and L⁵ represents a divalentaliphatic hydrocarbon group. L², L³ and L⁵ may be the same or different.Each of L² to L⁴ preferably represents an alkylene group, an alkenylenegroup, an alkynylene group or an arylene group, and L⁵ preferablyrepresents an alkylene group. Also, in L² to L⁵, another bond orfunctional group incapable of reacting with the isocyanate group, suchas ether bond, carbonyl bond, ester bond, cyano group, olefin bond,urethane bond, amide group, ureido group and halogen atom, may bepresent. Each of n1 and n2 represents an integer of 2 or more,preferably an integer of 2 to 100.

The polycarbonate diol compound includes a compound represented byformula (10).

In formula (10), L⁶s may be the same as or different from every othersand each represents a divalent aliphatic or aromatic hydrocarbon group.L⁶ preferably represents an alkylene group, an alkenylene group, analkynylene group or an arylene group. Also, in L⁶, another bond orfunctional group incapable of reacting with the isocyanate group, suchas ether bond, carbonyl group, ester bond, cyano group, olefin bond,urethane bond, amide bond, ureido group and halogen atom, may bepresent. n3 represents an integer of 2 or more, preferably an integer of2 to 100.

Specific examples of the diol compound represented by formula (8), (9)or (10) include (Compound No. 1) to (Compound No. 18) illustrated below.In specific examples, n represents an integer of 2 or more.

In the synthesis of the urethane-based resin, other than theabove-described diol compounds, a diol compound having a substituentincapable of reacting with the isocyanate group may be also used incombination. This diol compound includes, for example, the followings:HO-L⁷-O—CO-L⁸-CO—O-L⁷-OH  (11)HO-L⁸-CO—O-L⁷-OH  (12)

In formulae (11) and (12), each of L⁷ and L⁸, which may be the same ordifferent, represents a divalent aliphatic hydrocarbon group, anaromatic hydrocarbon group or a heterocyclic group. If desired, in L⁷and L⁸, another bond or functional group incapable of reacting with theisocyanate group, such as carbonyl group, ester bond, urethane bond,amide bond and ureido group, may be present. Incidentally, L⁷ and L⁸ mayform a ring.

The divalent aliphatic hydrocarbon group, aromatic hydrocarbon group andheterocyclic group may have a substituent, and examples of thesubstituent include an alkyl group, an aralkyl group, an aryl group, analkoxy group, an aryloxy group, and a halogen atom such as —F, —Cl, —Brand —I.

At least one of the diol compound is preferably an acid group-containingdiol compound as the above-described diol compound having a substituentincapable of reacting with the isocyanate group. Specific examples ofthe acid group include those described above, but the acid group ispreferably a carboxylic acid. The diol compound having a carboxylic acidgroup includes, for example, those represented by the following formulae(13) to (15)

In formulae (13) to (15), R¹⁵ represents a hydrogen atom, an alkylgroup, an aralkyl group, an aryl group, an alkoxy group or an aryloxygroup, preferably a hydrogen atom, an alkyl group having a carbon number1 to 8, or an aryl group having a carbon number 6 to 15.

The alkyl group, aralkyl group, aryl group, alkoxy group and aryloxygroup may have a substituent, and examples of the substituent include acyano group, a nitro group, a halogen atom such as —F, —Cl, —Br and —I,—CONH₂, —COOR¹⁶, —OR¹⁶, —NHCONHR¹⁶, —NHCOOR¹⁶, —NHCOR¹⁶, —OCONHR¹⁶(wherein R¹⁶ represents an alkyl group having a carbon number of 1 to 10or an aralkyl group having a carbon number of 7 to 15).

Each of L⁹, L¹⁰ and L¹¹, which may be the same or different, representsa single bond or a divalent aliphatic or aromatic hydrocarbon group,preferably an alkylene group having a carbon number of 1 to 20 or anarylene group having a carbon number of 6 to 15, more preferably analkylene group having a carbon number of 1 to 8.

The divalent aliphatic or aromatic hydrocarbon group may have asubstituent, and examples of the substituent include an alkyl group, anaralkyl group, an aryl group, an alkoxy group, and a halogen atom.

If desired, each of L⁹ to L¹¹ may have a group containing anotherfunctional group incapable of reacting with the isocyanate group, suchas carbonyl group, ester group, urethane group, amide group, ureidogroup and ether group. Incidentally, two or three members out of R¹⁵,L⁷, L⁸ and L⁹ may form a ring. Ar represents a trivalent aromatichydrocarbon group which may have a substituent, and preferablyrepresents an aromatic group having a carbon number of 6 to 15.

Specific examples of the carboxyl group-containing diol compoundsrepresented by formulae (13) to (15) include the followings:

that is, 3,5-dihydroxybenzoic acid, 2,2-bis(hydroxymethyl)propionicacid, 2,2-bis(2-hydroxyethyl)propionic acid,2,2-bis(3-hydroxypropyl)propionic acid, bis(hydroxymethyl)acetic acid,bis(4-hydroxyphenyl)acetic acid, 2,2-bis(hydroxymethyl)butyric acid,4,4-bis(4-hydroxyphenyl)pentanoic acid, tartaric acid,N,N-dihydroxyethylglycine, andN,N-bis(2-hydroxyethyl)-3-carboxy-propionamide.

The presence of such a carboxyl group is preferred becausecharacteristics such as hydrogen bonding property and alkali solubilitycan be imparted to the polyurethane resin.

In particular, a polyurethane resin having a carboxyl group in an amountof 0.5 to 4.0 meq/g, preferably from 1.0 to 3.0 meq/g, is preferred asthe binder polymer for use in the present invention.

In the case where the diol compound represented by formula (2) has acrosslinking group, a method using an unsaturated group-containing diolcompound as a raw material for the production of a polyurethane resin isalso preferred. Such a diol compound may be, for example, a commerciallyavailable product such as trimethylolpropane monoallyl ether, or acompound easily produced by the ration of a halogenated diol compound, atriol compound or an aminodiol compound with an unsaturatedgroup-containing carboxylic acid, an acid chloride, an isocyanate, analcohol, an amine, a thiol or an alkyl halide compound. Specificexamples of the crosslinking group-containing diol compound include, butare not limited to, those described in paragraphs [0057] to [0066] ofJapanese Patent 4,401,262.

Incidentally, the compounds illustrated as Compound Nos. 13 to 17 comeunder the diol compound represented by formula (8), (9) or (10) and atthe same time, are a crosslinking group-containing diol compound.

In particular, a polyurethane resin having a crosslinking group(preferably an ethylenically unsaturated bond group) in an amount of 0.5meq/g or more, preferably from 1.0 to 3.0 meq/g, is preferred as thebinder polymer for use in the present invention.

In the synthesis of the urethane-based resin, other than these diols, acompound obtained by ring-opening a tetracarboxylic acid dianhydriderepresented by any one of the following formulae (16) to (18) with adiol compound may be used in combination.

In formulae (16) to (18), L¹² represents a single bond, a divalentaliphatic or aromatic hydrocarbon group which may have a substituent(preferably, for example, an alkyl group, an aralkyl group, an arylgroup, an alkoxy group, a halogeno group, an ester group or an amidogroup), —CO—, —SO—, —SO₂—, —O— or —S—, preferably a single bond, adivalent aliphatic hydrocarbon group having a carbon number of 1 to 15,—CO—, —SO₂—, —O— or —S—.

The divalent aliphatic or aromatic hydrocarbon group may have asubstituent, and examples of the substituent include an alkyl group, anaralkyl group, an aryl group, an alkoxy group, a halogen atom, an esterbond-containing group (e.g., alkylcarbonyloxy group, alkyloxycarbonylgroup, arylcarbonyloxy group, aryloxycarbonyl group), and an amidogroup.

Each of R¹⁷ and R¹⁸, which may be the same or different, represents ahydrogen atom, an alkyl group, an aralkyl group, an aryl group, analkoxy group or a halogeno group, preferably a hydrogen atom, an alkylgroup having a carbon number of 1 to 8, an aryl group having a carbonnumber of 6 to 15, an alkoxy group having a carbon number of 1 to 8, ora halogen group.

Two members out of L¹², R¹⁷ and R¹⁸ may combine to form a ring.

Each of R¹⁹ and R²⁰, which may be the same or different, represents ahydrogen atom, an alkyl group, an aralkyl group, an aryl group or ahalogeno group, preferably a hydrogen atom, an alkyl group having acarbon number of 1 to 8, or an aryl group having a carbon number of 6 to15.

Two members out of L¹², R¹⁹, and R²⁰ may combine to form a ring.

Each of L¹³ and L¹⁴, which may be the same or different, represents asingle bond, a double bond or a divalent aliphatic hydrocarbon group,preferably a single bond, a double bond or a methylene group. Arepresents a mononuclear or polynuclear aromatic ring, preferably anaromatic ring having a carbon number of 6 to 18.

Specific examples of the compound represented by formula (16), (17) or(18) include the followings: that is, an aromatic tetracarboxylicdianhydride such as pyromellitic dianhydride,3,3′,4,4′-benzophenonetetracarboxylic dianhydride,3,3′,4,4′-diphenyltetracarboxylic dianhydride,2,3,6,7-naphthalenetetracarboxylic dianhydride,1,4,5,8-naphthalenetetracarboxylic dianhydride, 4,4′-sulfonyldiphthalicdianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride,bis(3,4-dicarboxyphenyl)ether dianhydride,4,4′-[3,3′-(alkylphosphoryldiphenylene)-bis(iminocarbonyl)]diphthalicdianhydride, adduct of hydroquinone diacetate and trimellitic anhydride,and adduct of diacetyldiamine and trimellitic anhydride; an alicyclictetracarboxylic dianhydride such as5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylicanhydride (EPICLON B-4400, produced by DIC Corporation),1,2,3,4-cyclopentanetetracarboxylic dianhydride,1,2,4,5-cyclohexanetetracarboxylic dianhydride, andtetrahydrofurantetracarboxylic dianhydride; and an aliphatictetracarboxylic dianhydride such as 1,2,3,4-butanetetracarboxylicdianhydride and 1,2,4,5-pentanetetracarboxylic dianhydride.

Examples of the method for introducing a compound obtained byring-opening such a tetracarboxylic dianhydride with a diol compoundinto the polyurethane resin include the following methods:

a) a method of reacting a diisocyanate compound with analcohol-terminated compound obtained by ring-opening the tetracarboxylicdianhydride with a diol compound, and

b) a method of reacting the tetracarboxylic dianhydride with analcohol-terminated urethane compound obtained by reacting a diisocyanatecompound under diol compound-excess conditions.

Specific examples of the diol compound used for the ring-openingreaction include the followings:

that is, ethylene glycol, diethylene glycol, triethylene glycol,tetraethylene glycol, propylene glycol, dipropylene glycol, polyethyleneglycol, polypropylene glycol, neopentyl glycol, 1,3-butylene glycol,1,6-hexanediol, 2-butene-1,4-diol, 2,2,4-trimethyl-1,3-pentanediol,1,4-bis-β-hydroxyethoxycyclohexane, cyclohexanedimethanol,tricyclodecanedimethanol, hydrogenated bisphenol A, hydrogenatedbisphenol F, an ethylene oxide adduct of bisphenol A, a propylene oxideadduct of bisphenol A, an ethylene oxide adduct of bisphenol F, apropylene oxide adduct of bisphenol F, an ethylene oxide adduct ofhydrogenated bisphenol A, a propylene oxide adduct of hydrogenatedbisphenol A, hydroquinonedihydroxyethyl ether, p-xylylene glycol,dihydroxyethylsulfone, bis(2-hydroxyethyl)-2,4-tolylene dicarbamate,2,4-tolylene-bis(2-hydroxyethylcarbamide),bis(2-hydroxyethyl)-m-xylylene dicarbamate, andbis(2-hydroxyethyl)isophthalate.

The urethane-based resin described above is synthesized by adding thosediisocyanate and diol compounds and a known catalyst having an activityaccording to the reactivity of respective compounds in an aproticsolvent and heating the solution. The molar ratio (M_(a):M_(b)) of thediisocyanate and diol compounds used for the synthesis is preferablyfrom 1:1 to 1.2:1. A product having desired physical properties such asmolecular weight and viscosity is preferably synthesized finally in theform of allowing no isocyanate group to remain by applying a treatmentwith alcohols or amines.

A urethane-based resin having a crosslinking group (for example, anunsaturated group) in the polymer terminal and main chain is alsopreferably used. By having a crosslinking group in the polymer terminaland main chain, the crosslinking reactivity is more enhanced between thepolymerizable compound and the urethane-based resin or betweenurethane-based resins, and the strength of the permanent pattern isincreased. In view of easy occurrence of a crosslinking reaction, theunsaturated group preferably contains a carbon-carbon double bond.

The method for introducing a crosslinking group into the polymerterminal includes the following method. That is, in the step of treatingthe residual isocyanate group at the polymer terminal with alcohols,amines or the like in the process of synthesizing the polyurethaneresin, alcohols, amines or the like having a crosslinking group may beused. Specific examples of such a compound include the same compounds asthose exemplified above for the monofunctional alcohol or monofunctionalamine compound having a crosslinking group.

Incidentally, the crosslinking group is preferably introduced into thepolymer side chain rather than into the polymer terminal, because theamount of the crosslinking group introduced can be easily controlled andcan be increased and also, the crosslinking reaction efficiency isenhanced.

The method for introducing a crosslinking group into the main chainincludes a method of using a diol compound having an unsaturated groupin the main chain direction for the synthesis of the polyurethane resin.Specific examples of the diol compound having an unsaturated group inthe main chain direction include the following compounds: that is,cis-2-butene-1,4-diol, trans-2-butene-1,4-diol, and polybutadiene diol.

As the alkali-soluble binder other than the (meth)acrylic resin and theurethane-based resin, an acetal-modified polyvinyl alcohol-based binderpolymer having an acid group described, for example, in European Patents993,966 and 1,204,000 and JP-A-2001-318463 is preferred because ofexcellent balance between film strength and developability. In addition,a water-soluble linear organic polymer such as polyvinylpyrrolidone andpolyethylene oxide is useful. Also, an alcohol-soluble nylon, apolyether of 2,2-bis-(4-hydroxyphenyl)-propane and epichlorohydrin, andthe like are useful for increasing the strength of the cured film.

Above all, a [benzyl (meth)acrylate/(meth)acrylic acid/if desired,another addition-polymerizable vinyl monomer] copolymer, and a [allyl(meth)acrylate/(meth)acrylic acid/if desired, anotheraddition-polymerizable vinyl monomer] copolymer are preferred because ofexcellent balance among film strength, sensitivity and developability.

The weight average molecular weight of the binder polymer which can beused in the polymerizable composition of the present invention ispreferably 3,000 or more, more preferably from 5,000 to 300,000, andmost preferably from 10,000 to 30,000, and the number average molecularweight is preferably 1,000 or more, more preferably from 2,000 to250,000. The polydispersity (weight average molecular weight/numberaverage molecular weight) is preferably 1 or more, more preferably from1.1 to 10.

The binder polymer may be any of a random polymer, a block polymer, agraft polymer and the like.

The alkali-soluble binder can be synthesized by a conventionally knownmethod. Examples of the solvent used at the synthesis includetetrahydrofuran, ethylene dichloride, cyclohexanone, propylene glycolmonomethyl ether, propylene glycol monomethyl ether acetate, and butylacetate. One of these solvents may be used alone, or two o more thereofmay be mixed and used.

The content of the alkali-soluble binder is preferably from 5 to 80 mass%, more preferably from 30 to 60 mass %, based on the entire solidcontent by mass of the polymerizable composition of the presentinvention. With a content in this range, the exposure sensitivity isgood, the processing time can be short, and good TCT resistance isobtained.

[5] (E) Ultraviolet Absorber

The polymerizable composition of the present invention may contain (E)an ultraviolet absorber.

The ultraviolet absorber (E) is incorporated, for example, into a resistcomposition for solder resists and after forming a photosensitive layerby coating the resist composition on a semiconductor substrate forsolid-state imaging devices, where an alignment mark is provided on thesurface, exposure and development are performed to form a solder resistlayer, whereby a solder resist layer capable of satisfying bothelimination of the later-described “problem attributable to reflectedlight on the substrate surface” and unfailing detection of the alignmentmark by a visible light sensor can be more reliably produced.

In the case where the substrate surface having provided thereon aphotosensitive layer is formed of a material having high lightreflectivity, such as metal, the cross-sectional shape of the obtainedpattern is liable to become a skirt shape (that is, rectangularity ofthe cross-sectional shape is liable to be impaired), since reflectedlight from the substrate surfactant in exposure to the photosensitivelayer becomes considerable. On the other hand, in the case, if theexposure dose is kept low so as to reduce the reflected light, a patternhaving a rectangular cross-sectional shape can be hardly formed due toinsufficient exposure dose.

However, in the case where the polymerizable composition of the presentinvention contains the ultraviolet absorber (E), even when irradiationis performed with an exposure dose necessary to obtain a pattern havinga rectangular cross-sectional shape (hereinafter, sometimes referred toas an “adequate exposure dose”), the ultraviolet absorber (E) absorbsthe reflected light and this makes it easy to form a pattern having arectangular cross-sectional shape.

As the ultraviolet absorber (E), any compound may be used. However, theultraviolet absorber (E) indicates a compound incapable of initiatingthe polymerization of a polymerizable compound by light or heat (thatis, a compound not coming under the polymerization initiator (A)). Theexpression “incapable of initiating the polymerization of apolymerizable compound” as used herein means that even when theultraviolet absorber (E) receives light or heat energy, it does notgenerate an active species for initiating the polymerization of apolymerizable compound.

To be more specific, the ultraviolet absorber (E) is preferably acompound having no photosensitivity to ultraviolet or visible ray (morespecifically, light at a wavelength of 300 to 450 nm) and having nothermosensitivity to heat (more specifically, for example, heat at 150to 250° C.). The terms “photosensitivity” and “thermosensitivity” asused herein mean to develop the objective function while involvingchange in the chemical structure by the effect of ultraviolet or visibleray or heat.

Furthermore, the ultraviolet absorber (E) is preferably not onlyincapable of initiating the polymerization of a polymerizable compoundbut also lacking in the property of the sensitizer described later. Theterm “property of the sensitizer” as used herein indicates the propertyof transferring energy obtained by light absorption of the sensitizeritself to another material (polymerization initiator) and therebyinitiating the polymerization.

The ultraviolet absorber (E) is preferably a compound having a maximumabsorption wavelength between 300 nm and 430 nm, more preferably acompound having a maximum absorption wavelength between 330 nm and 420nm.

The ultraviolet absorber (E) still more preferably has a maximumabsorption wavelength at least in one range out of (I) the range of 340to 380 nm, (II) the range of 380 to 420 nm, and (III) the range of 420to 450 nm.

At the time of forming a pattern by applying exposure and development tothe photosensitive layer formed using the polymerizable composition ofthe present invention, in the case where the light source for exposurecontains i-line, the ultraviolet absorber (E) preferably has a maximumabsorption wavelength in the wavelength range (I) above.

In the case where the light source for exposure contains h-line, theultraviolet absorber (E) preferably has a maximum absorption wavelengthin the wavelength range (II) above.

In the case where the light source for exposure contains g-line, theultraviolet absorber (E) preferably has a maximum absorption wavelengthin the wavelength range (III) above.

As the ultraviolet absorber, for example, a salicylate-based,benzophenone-based, benzotriazole-based, substituted acrylonitrile-basedor triazine-based ultraviolet absorber may be used.

Examples of the salicylate-based ultraviolet absorber include phenylsalicylate, p-octylphenyl salicylate and p-tert-butylphenyl salicylate.Examples of the benzophenone-based ultraviolet absorber include2,2′-dihydroxy-4-methoxybenzophenone,2,2′-dihydroxy-4,4′-dimethoxybenzophenone,2,2′,4,4′-tetrahydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone,2,4-dihydroxybenzophenone and 2-hydroxy-4-octoxybenzophenone. Examplesof the benzotriazole-based ultraviolet absorber include2-(2′-hydroxy-3′,5′-di-tert-butylphenyl)-5-chlorobenzotriazole,2-(2′-hydroxy-3′-tert-butyl-5′-methylphenyl)-5-chlorobenzotriazole,2-(2′-hydroxy-3′-tert-amyl-5′-isobutylphenyl)-5-chlorobenzotriazole,2-(2′-hydroxy-3′-isobutyl-5′-methylphenyl)-5-chlorobenzotriazole,2-(2′-hydroxy-3 sobutyl-5′-propylphenyl)-5-chlorobenzotriazole,2-(2′-hydroxy-3′,5′-di-tert-butylphenyl)benzotriazole,2-(2′-hydroxy-5′-methylphenyl)benzotriazole, and2-[2′-hydroxy-5′-(1,1,3,3-tetramethyl)phenyl]benzotriazole.

Examples of the substituted acrylonitrile-based ultraviolet absorberinclude ethyl 2-cyano-3,3-diphenylacrylate and 2-ethylhexyl2-cyano-3,3-diphenylacrylate. Examples of the triazine-based ultravioletabsorber include a mono(hydroxyphenyl)triazine compound such as2-[4-[(2-hydroxy-3-dodecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine,2-[4-[(2-hydroxy-3-tridecyloxypropyl)oxy]-2-hydroxyphenyl]-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazineand 2-(2,4-dihydroxyphenyl)-4,6-bis(2,4-dimethylphenyl)-1,3,5-triazine;a bis(hydroxyphenyl)triazine compound such as2,4-bis(2-hydroxy-4-propyloxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazine,2,4-bis(2-hydroxy-3-methyl-4-propyloxyphenyl)-6-(4-methylphenyl)-1,3,5-triazineand2,4-bis(2-hydroxy-3-methyl-4-hexyloxyphenyl)-6-(2,4-dimethylphenyl)-1,3,5-triazine;and a tris(hydroxyphenyl)triazine compound such as2,4-bis(2-hydroxy-4-butoxyphenyl)-6-(2,4-dibutoxyphenyl)-1,3,5-triazine,2,4,6-tris(2-hydroxy-4-octyloxyphenyl)-1,3,5-triazine and2,4,6-tris[2-hydroxy-4-(3-butoxy-2-hydroxypropyloxy)phenyl]-1,3,5-triazine.

The ultraviolet absorber is preferably a compound represented by thefollowing formula (A):

In the formula, each of R₆₁ and R₆₂ independently represents a hydrogenatom, an alkyl group, an aryl group, or a nonmetallic atom groupnecessary for forming a 5- or 6-membered ring by combining with eachother. Also, either one of R₆₁ and R₆₂ may combine with the methinegroup next to the nitrogen atom to form a 5- or 6-membered ring. Each ofX₆₁ and Y₆₁ independently represents a cyano group, —COOR₆₃, —CONR₆₃R₆₄,—COR₆₃, —SO₂R₆₃ or —SO₂R₆₃R₆₄, and each of R₆₃ and R₆₄ independentlyrepresents a hydrogen atom, an alkyl group or an aryl group. X₆₁ and Y₆₁may combine with each other to form a 5- or 6-membered ring.Furthermore, any one of R₆₁, R₆₂, X₆₁ and Y₆₁ may combine with any oneof R₆₁, R₆₂, X₆₁ and Y₆₁ in another compound represented by formula (A)to form a dimer.

In the present invention, one of these various ultraviolet absorbers maybe used alone, or two or more thereof may be used in combination.

The polymerizable composition of the present invention may or may notcontain the ultraviolet absorber (E) but in the case of containing theultraviolet absorber, the content thereof is preferably from 0.001 to 1mass %, more preferably from 0.01 to 0.3 mass %, based on the entiresolid content by mass of the polymerizable composition of the presentinvention.

[6] Infrared-Blocking Material Other than Tungsten Compound and MetalBoride

The polymerizable composition of the present invention may contain aninfrared-blocking material other than a tungsten compound and a metalboride (hereinafter, sometimes referred to as “the otherinfrared-blocking material”) within the range not impairing the effectsof the present invention. The other infrared-blocking material ispreferably a compound having absorption at a wavelength of 800 to 1,200nm and exhibiting good transparency to light used for exposure, and fromsuch viewpoints, the other infrared-blocking material is preferablyselected from infrared-absorbing dyestuffs and infrared-absorbentinorganic pigments.

Examples of the infrared-absorbing dyestuff include a cyanine dye, aphthalocyanine dye, a naphthalocyanine dye, an immonium dye, an aminiumdye, a quinolium dye, a pyrylium dye, and a metal complex dye such as Nicomplex dye.

The dye usable as the infrared-blocking material is also available as acommercial product, and preferred examples thereof include the followingcommercially available dyes:

S0345, S0389, S0450, S0253, S0322, S0585, S0402, S0337, S0391, S0094,S0325, S0260, S0229, S0447, S0378, S0306 and S0484 produced by FEWChemicals; ADS795WS, ADS805WS, ADS819WS, ADS820WS, ADS823WS, ADS830WS,ADS850WS, ADS845MC, ADS870MC, ADS880MC, ADS890MC, ADS920MC, ADS990MC,ADS805PI, ADSW805PP, ADS81000, ADS813MT, ADS815EI, ADS816EI, ADS818HT,ADS819MT, ADS819MT, ADS821NH, ADS822MT, ADS838MT, ADS840MT, ADS905AM,ADS956BP, ADS1040P, ADS1040T, ADS1045P, ADS1040P, ADS1050P, ADS1065A,ADS1065P, ADS1100T and ADS1120F produced by American Dye Source, Inc.;

YKR-4010, YKR-3030, YKR-3070, MIR-327, MIR-371, SIR-159, PA-1005,MIR-369, MIR-379, SIR-128, PA-1006, YKR-2080, MIR-370, YKR-3040,YKR-3081, SIR-130, MIR-362, YKR-3080, SIR-132 and PA-1001 produced byYamamoto Chemical Industry Co., Ltd.; and

NK-123, NK-124, NK-1144, NK-2204, NK-2268, NK-3027, NKX-113, NKX-1199,NK-2674, NK-3508, NKX-114, NK-2545, NK-3555, NK-3509 and NK-3519produced by Hayashibara Biochemical Labs, Inc.

Among these dyes, in view of heat resistance, a phthalocyanine dye and ametal complex dye are preferred.

One of these dyes may be used alone, or for the purpose of bringing outgood light-blocking effect at a wavelength of 800 to 1,200 nm, two ormore dyes according to this purpose may be mixed and used.

Examples of the infrared-absorbent inorganic pigment which can be usedas the other infrared-blocking material include zinc flower, lead white,lithopone, titanium oxide, chromium oxide, precipitating barium sulfate,barite powder, red lead, iron oxide red, lead yellow, zinc yellow (type1 zinc yellow, type 2 zinc yellow), ultramarine blue, Prussian blue(iron/potassium ferrocyanide), zircon grey, praseodymium yellow,chrome-titanium yellow, chrome green, peacock blue, Victoria green, ironblue (irrelevant to Prussian blue), vanadium-zirconium blue, chrome-tinpink, manganese pink and salmon pink. Furthermore, as a black pigment,for example, a metal oxide, a metal nitride or a mixture thereof eachcontaining one metal element or two or more metal elements selected fromthe group consisting of Co, Cr, Cu, Mn, Ru, Fe, Ni, Sn, Ti and Ag, maybe used.

The black pigment is preferably titanium black that is a titaniumnitride-containing black pigment, because shielding property in theinfrared region at a wavelength of 800 to 1,200 nm is good.

Titanium black can be obtained by a conventionally known method, and asthe commercially available product, titanium black produced, forexample, by Ishihara Sangyo Kaisha, Ltd., Ako Kasei Co., Ltd., JEMCOInc., Mitsubishi Materials Corp., or Mitsubishi Materials ElectronicChemicals Co., Ltd. may be used.

Titanium black indicates a black particle having a titanium atom, andlow-order titanium oxide, titanium oxynitride or the like is preferred.As the titanium black particle, a surface-modified particle may be used,if desired, for the purpose of improving dispersibility, preventingaggregation, or the like.

The surface modification method includes a method of covering thesurface with one or more members selected from silicon oxide, titaniumoxide, germanium oxide, aluminum oxide, magnesium oxide, and zirconiumoxide. Also, the surface may be treated with a water-repellent substancedescribed in paragraphs [0010] to [0027] of JP-A-2007-302836.

Examples of the method for producing titanium black include, but are notlimited to, a method of reducing a mixture of titanium dioxide and metaltitanium by heating it in a reductive atmosphere (JP-A-49-5432); amethod of reducing ultrafine titanium dioxide obtained byhigh-temperature hydrolysis of titanium tetrachloride, in a reductiveatmosphere containing hydrogen (JP-A-57-205322); a method of reducingtitanium dioxide or titanium hydroxide at high temperature in thepresence of ammonia (JP-A-60-65069, JP-A-61-201610); and a method ofattaching a vanadium compound to titanium dioxide or titanium hydroxideand then reducing it at high temperature in the presence of ammonia(JP-A-61-201610).

The particle diameter of the titanium black particle is not particularlylimited but in view of dispersibility and colorability, the particlediameter is preferably from 3 to 2,000 nm, more preferably from 10 to500 nm.

The specific surface area of titanium black is not particularly limited,but usually, the value measured by the BET method is preferably on theorder of 5 to 150 m²/g, more preferably on the order of 20 to 100 m²/g,because titanium black after surface treatment with a water-repellentagent can have a predetermined performance in terms of water repellency.

With respect to the particle diameter of the inorganic pigment used asthe other infrared-blocking material, the average particle diameter ispreferably from 3 nm to 0.01 mm, and in view of dispersibility,light-blocking effect and precipitation with aging, the average particlediameter is preferably from 10 nm to 1 μm.

The polymerizable composition may or may not contain the otherinfrared-blocking material but in the case of containing the otherinfrared-blocking material, the content thereof is preferably from 5 to75 mass %, more preferably from 10 to 40 mass %, based on the mass ofthe compound (C).

[7] Dispersant

In the present invention, when the compound (C) is particularly a fineparticle (that is, when the tungsten compound is particularly a tungstenfine particle, or when the metal boride is particularly a metal boridefine particle), the fine particle may be dispersed using a knowndispersant for the purpose of enhancing the dispersibility anddispersion stability of the compound (C) in the polymerizablecomposition.

As the dispersant, for example, a known dispersant or surfactant may beappropriately selected and used.

Specifically, many kinds of compounds are usable, and examples thereofinclude a cationic surfactant such as Organosiloxane Polymer KP341(produced by Shin-Etsu Chemical Co.), (meth)acrylic acid-based(co)polymer Polyflow No. 75, No. 90 and No. 95 (produced by KyoeishaChemical Co., Ltd.), and WO01 (produced by Yusho Co., Ltd.); a nonionicsurfactant such as polyoxyethylene lauryl ether, polyoxyethylene stearylether, polyoxyethylene oleyl ether, polyoxyethylene octylphenyl ether,polyoxyethylene nonylphenyl ether, polyethylene glycol dilaurate,polyethylene glycol distearate, and sorbitan fatty acid ester; ananionic surfactant such as WO04, WO05 and WO17 (produced by Yusho Co.,Ltd.); a polymer dispersant such as EFKA-46, EFKA-47, EFKA-47EA, EFKAPOLYMER 100, EFKA POLYMER 400, EFKA POLYMER 401, EFKA POLYMER 450 (allproduced by BASF Japan); various Soisperse dispersants such as SOLSPERSE3000, 5000, 9000, 12000, 13240, 13940, 17000, 24000, 26000, 28000, 32000and 36000 (produced by The Lubrizol Corporation); ADEKA PLURONIC L31,F38, L42, L44, L61, L64, F68, L72, P95, F77, P84, F87, P94, L101, P103,F108, L121 and P-123 (produced by ADEKA), ISONET S-20 (produced by SanyoChemical Industries, Ltd.), and Disperbyk 101, 103, 106, 108, 109, 111,112, 116, 130, 140, 142, 162, 163, 164, 166, 167, 170, 171, 174, 176,180, 182, 2000, 2001, 2050 and 2150 (produced by BYK Chemie Japan).Other examples include an oligomer or polymer having a polar group inthe molecular terminal or side chain, such as acrylic copolymer.

In view of dispersibility, developability, precipitation, the followingresins described in JP-A-2010-106268 are preferred, and particularly inview of dispersibility, a polymer dispersant having a polyester chain inthe side chain is preferred. Also, in view of dispersibility andresolution of a pattern formed by photolithography, a resin having anacid group and a polyester chain is preferred. As the acid group in thedispersant, in view of adsorptive property, an acid group with pKa of 6or less is preferred, and a carboxylic acid, a sulfonic acid or aphosphoric acid is more preferred.

The dispersant resin described in JP-A-2010-106268, which is preferablyused in the present invention, is described below.

The dispersant resin is preferably a graft copolymer containing, in themolecule, a graft chain having a number of atoms, excluding hydrogenatom, of 40 to 10,000 and being selected from a polyester structure, apolyether structure and a polyacrylate structure, which is a graftcopolymer containing a structural unit represented by any one of thefollowing formulae (1) to (5).

[In Formulae (1) to (5), each of X¹, X², X³, X⁴, X⁵ and X⁶ independentlyrepresents a hydrogen atom or a monovalent organic group, each of Y¹,Y², Y³, Y⁴ and Y⁵ independently represents a divalent linking group,each of Z¹, Z², Z³, Z⁴ and Z⁵ independently represents a hydrogen atomor a monovalent organic group, R represents a hydrogen atom or amonovalent organic group, Rs differing in the structure may be presentin the copolymer, each of n, m, p, q and r represents an integer of 1 to500, and each of j and k independently represents an integer of 2 to 8.]

Among these, a compound having a polyester chain in the side chain,represented by formula (1), is preferred. Representative examplesthereof include Exemplified Compounds 1 to 71 illustrated in paragraphs[0046] to [0078] in JP-A-2010-106268, and these may be suitably used asa dispersant also in the present invention.

Exemplified Compounds 1 to 50 are illustrated below as the dispersantsuitable for the present invention, but the present invention is notlimited thereto. In the compounds illustrated below, the numerical valueattached to each structural unit (numerical value attached to themain-chain repeating unit) indicates the content [mass %; shown as (wt%)] of the structural unit. The numerical value attached to theside-chain repeating moiety indicates the repetition number of therepeating moiety.

In view of dispersibility, developability and precipitation property, aresin having a polyester chain in the side chain is preferred, and inview of dispersibility and resolution property, a resin further havingan acid group is preferred. The acid group is, in view of adsorptiveproperty, preferably an acid group having pKa of 6 or less, morepreferably an acid group derived from a carboxylic acid, a sulfonic acidor a phosphoric acid.

In view of solubility in the dispersion solution as well asdispersibility and developability, a resin having a carboxylic acidgroup, where the polyester chain is a polycaprolactone side chain, ismost preferred.

An amphoteric surfactant such as Hinoact T-8000E produced by KawakenFine Chemicals, Ltd. may be also used as the dispersant.

In the case of using a dispersant, from the standpoint of enhancing thedispersibility, a dispersion composition is preferably prepared usingthe compound (C) (and the other infrared-blocking material, if desired),a dispersant and an appropriate solvent and then blended in thepolymerizable composition.

The polymerizable composition may or may not contain a dispersant, butin the case of containing a dispersant, the content thereof in thedispersion composition is preferably from 1 to 90 mass %, morepreferably from 3 to 70 mass %, based on the entire solid content bymass of the compound (C) in the dispersion composition or in the case ofusing the other infrared-blocking material and using aninfrared-absorbent inorganic pigment as the other infrared-blockingmaterial, based on the sum of the entire solid contents by mass of thecompound (C) and the infrared-absorbent inorganic pigment.

[8] Sensitizer

The polymerizable composition of the present invention may contain asensitizer for the purpose of enhancing the radical generatingefficiency of the polymerization initiator and shifting thephotosensitive wavelength to the longer wavelength side. The sensitizerwhich can be used in the present invention is preferably a sensitizercapable of sensitizing the photopolymerization initiator by an electrontransfer mechanism or an energy transfer mechanism. The sensitizer whichcan be used in the present invention includes those belonging to thecompounds enumerated below and having an absorption wavelength in thewavelength region of 300 to 450 nm.

Preferred examples of the sensitizer include those belonging to thefollowing compounds and having an absorption wavelength in thewavelength region of 330 to 450 nm.

Examples include a polynuclear aromatic compound (e.g., phenanthrene,anthracene, pyrene, perylene, triphenylene, 9,10-dialkoxyanthracene), axanthene-based compound (e.g., fluorescein, eosin, erythrosine,Rhodamine B, Rose Bengal), a thioxanthone-based compound (e.g.,isopropylthioxanthone, diethylthioxanthone, chlorothioxanthone), anacridone-based compound (e.g., acridone, chloroacridone,N-methylacridone, N-butylacridone, 10-n-butyl-2-chloroacridone), acyanine-based compound (e.g., thiacarbocyanine, oxacarbocyanine), amerocyanine-based compound (e.g., merocyanine, carbomerocyanine), aphthalocyanine-based compound, a thiazine-based compound (e.g.,thionine, methylene blue, toluidine blue), an acridine-based compound(e.g., acridine orange, chloroflavin, acriflavin), ananthraquinone-based compound (e.g., anthraquinone), a squarylium-basedcompound (e.g., squarylium), acridine orange, a coumarin-based compound(e.g., coumarin, 7-diethylamino-4-methylcoumarin), ketocoumarin, aphenothiazine-based compound, a phenazine-based compound, astyrylbenzene-based compound, an azo compound, diphenylmethane,triphenylmethane, distyrylbenzene-based compound, a carbazole-basedcompound, porphyrin, a spiro compound, quinacridone, indigo, styryl, apyrylium compound, a pyromethene compound, a pyrazolotriazole compound,a benzothiazole compound, a barbituric acid derivative, a thiobarbituricacid derivative, an aromatic ketone compound such as acetophenone,benzophenone, thioxanthone and Michler's ketone, and a heterocycliccompound such as N-aryl oxazolidinone.

Examples further include compounds described in European Patent 568,993,U.S. Pat. Nos. 4,508,811 and 5,227,227, JP-A-2001-125255 andJP-A-11-271969.

Above all, the sensitizer is preferably at least one member selectedfrom a thioxanthone-based compound, an acridone-based compound and acoumarin-based compound, and by combining such a sensitizer with theabove-described polymerization initiator, high sensitivity can be morereliably obtained.

The polymerizable composition may or may not contain the sensitizer butin the case of containing the sensitizer, the content thereof ispreferably from 0.01 to 10 mass %, more preferably from 0.1 to 2 mass %,based on the entire solid content by mass of the polymerizablecomposition of the present invention.

[9] Crosslinking Agent

The polymerizable composition of the present invention may furthercontain a crosslinking agent for the purpose of enhancing the strengthof the permanent pattern.

The crosslinking agent is not particularly limited as long as it is acompound having a crosslinking group, and the compound preferably hastwo or more crosslinking groups. Specific preferred examples of thecrosslinking group include an oxetane group, a cyanate group, and thesame groups as those described for the crosslinking group which thealkali-soluble binder may have. Among these, an epoxy group, an oxetanegroup and a cyanate group are preferred. That is, the crosslinking groupis preferably an epoxy compound, an oxetane compound or a cyanatecompound.

Examples of the epoxy compound which can be suitably used as thecrosslinking agent in the present invention include an epoxy compoundcontaining at least two oxirane groups per molecule, and an epoxycompound containing, per molecule, at least two epoxy groups each havingan alkyl group at the β-position.

Examples of the epoxy compound having at least two oxirane groups permolecule include, but are not limited to, a bixylenol-type orbiphenol-type epoxy compound (e.g., “YX4000 produced by Japan EpoxyResins Co., Ltd.”), a mixture thereof, a heterocyclic epoxy compoundhaving an isocyanurate framework or the like (e.g., “TEPIC produced byNissan Chemicals Industries, Ltd.”, “ARALDITE PT810 produced by BASFJapan”), a bisphenol A-type epoxy compound, a novolak-type epoxycompound, a bisphenol F-type epoxy compound, a hydrogenated bisphenolA-type epoxy compound, a bisphenol S-type epoxy compound, a phenolnovolak-type epoxy compound, a cresol novolak-type epoxy compound, ahalogenated epoxy compound (such as low brominated epoxy compound, highhalogenated epoxy compound, brominated phenol novolak-type epoxycompound), an allyl group-containing bisphenol A-type epoxy compound, atrisphenolmethane-type epoxy compound, a diphenyldimethanol-type epoxycompound, a phenol biphenylene-type epoxy compound, adicyclopentadiene-type epoxy compound (e.g., “HP-7200, HP-7200H producedby Dainippon Ink and Chemicals, Inc.”), a glycidylamine-type epoxycompound (such as diaminodiphenylmethane-type epoxy compound,glycidylaniline and triglycidylaminophenol), a glycidyl ester-type epoxycompound (e.g., diglycidyl phthalate, diglycidyl adipate, diglycidylhexahydrophthalate, diglycidyl dimerate), a hydantoin-type epoxycompound, an alicyclic epoxy compound (e.g.,3,4-epoxycyclohexylmethyl-3′,4′-epoxycyclohexanecarboxylate,bis(3,4-epoxycyclohexylmethyl)adipate, dicyclopentadiene diepoxide,“GT-300, GT-400, ZEHPE3150 produced by Daicel Chemical Industries,Ltd.”), an imide-type alicyclic epoxy compound, atrihydroxyphenylmethane-type epoxy compound, bisphenol A novolak-typeepoxy compound, a tetraphenylolethane-type epoxy compound, a glycidylphthalate compound, a tetraglycidyl xylenoylethane compound, anaphthalene group-containing epoxy compound (such as naphtholaralkyl-type epoxy compound, naphthol novolak-type epoxy compound,tetrafunctional naphthalene-type epoxy compound, and commerciallyavailable “ESN-190, ESN-360 produced by Nippon Steel Chemical Co.,Ltd.”, and “HP-4032, EXA-4750, EXA-4700 produced by Dainippon Ink andChemicals, Inc.”), a reaction produce of epichlorohydrin with apolyphenol compound obtained by an addition reaction between a phenolcompound and a diolefin compound such as divinylbenzene anddicyclopentadiene, a 4-vinylcyclohexene-1-oxide ring-openingpolymerization product epoxidized with peracetic acid or the like, anepoxy compound having a linear phosphorus-containing structure, an epoxycompound having a cyclic phosphorus-containing structure, anα-methylstilbene-type liquid crystal epoxy compound, adibenzoyloxybenzene-type liquid crystal epoxy compound, anazophenyl-type liquid crystal epoxy compound, an azomethine phenyl-typeliquid crystal epoxy compound, a binaphthyl-type liquid crystal epoxycompound, an azine-type epoxy compound, a glycidyl methacrylatecopolymer-based epoxy compound (e.g., “CP-50S, CP-50M produced by NOFCorporation”), a copolymerized epoxy compound of cyclohexyl maleimideand glycidyl methacrylate, a bis(glycidyloxyphenyl)fluorene-type epoxycompound, and a bis(glycidyloxyphenyl)adamantane-type epoxy compound.One of these epoxy resins may be used alone, or two or more thereof maybe used in combination.

Other than the epoxy compound containing at least two oxirane groups permolecule, an epoxy compound containing, per molecule, at least two epoxygroups each having an alkyl group at the β-position may be used, and acompound containing an epoxy group substituted with an alkyl group atthe β-position (more specifically, a β-alkyl-substituted glycidyl groupor the like) is particularly preferred.

In the epoxy compound containing at least an epoxy group having an alkylgroup at the β-position, all of two or more epoxy groups contained permolecule may be a β-alkyl-substituted glycidyl group, or at least oneepoxy group may be a β-alkyl-substituted glycidyl group.

Examples of the oxetane compound include an oxetane resin having atleast two oxetanyl groups per molecule.

Specific examples thereof include polyfunctional oxetanes such asbis[(3-methyl-3-oxetanylmethoxy)methyl]ether,bis[(3-ethyl-3-oxetanylmethoxy)methyl]ether,1,4-bis[(3-methyl-3-oxetanylmethoxy)methyl]benzene,1,4-bis[(3-ethyl-3-oxetanylmethoxy)methyl]benzene,(3-methyl-3-oxetanyl)methyl acrylate, (3-ethyl-3-oxetanyl)methylacrylate, (3-methyl-3-oxetanyl)methyl methacrylate,(3-ethyl-3-oxetanyl)methyl methacrylate, and an oligomer or copolymerthereof; and ether compounds of an oxetane group-containing compound anda hydroxyl group-containing resin such as novolak resin,polyp-hydroxystyrene), cardo-type bisphenols, calixarenes,calixresorcinarenes and silsesquioxane. Other examples include acopolymer of an oxetane ring-containing unsaturated monomer and an alkyl(meth)acrylate.

Examples of the bismaleimide compound include 4,4′-diphenylmethanebismaleimide, bis-(3-ethyl-5-methyl-4-maleimidophenyl)methane, and2,2′-bis-[4-(4-maleimidophenoxy)phenyl]propane.

Examples of the cyanate compound include a bis A-type cyanate compound,a bis F-type cyanate compound, a cresol novolak-type cyanate compound,and a phenol novolak-type cyanate compound.

The polymerizable composition may or may not contain a crosslinkingagent, but in the case of containing a crosslinking agent, the contentthereof is preferably from 1 to 40 mass %, more preferably from 3 to 20mass %, based on the entire solid content by mass of the polymerizablecomposition of the present invention.

[10] Curing Accelerator

The polymerizable composition of the present invention may furthercontain a curing accelerator for the purpose of accelerating thermalcuring of the crosslinking agent such as the above-described epoxycompound and oxetane compound.

Examples of the curing accelerator which can be used include an aminecompound (such as dicyandiamide, benzyldimethylamine,4-(dimethylamino)-N,N-dimethylbenzylamine,4-methoxy-N,N-dimethylbenzylamine and 4-methyl-N,N-dimethylbenzylamine),a quaternary ammonium salt compound (such as triethylbenzyl ammoniumchloride), a block isocyanate compound (such as dimethylamine), animidazole derivative-bicyclic amidine compound and a salt thereof (suchas imidazole, 2-methylimidazole, 2-ethylimidazole,2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole,1-cyanoethyl-2-phenylimidazole and1-(2-cyanoethyl)-2-ethyl-4-methylimidazole), a phosphorus compound (suchas triphenylphosphine), a guanamine compound (such as melamine,guanamine, acetoguanamine and benzoguanamine), and an S-triazinederivative (such as 2,4-diamino-6-methacryloyloxyethyl-S-triazine,2-vinyl-2,4-diamino-S-triazine,2-vinyl-4,6-diamino-S-triazine-isocyanuric acid adduct,2,4-diamino-6-methacryloyloxyethyl-S-triazine-isocyanuric acid adduct).These may be used alone or in combination. One of these compounds may beused alone, or two or more thereof may be used in combination.

The polymerizable composition may or may not contain a curingaccelerator, but in the case of containing a curing accelerator, thecontent thereof is usually from 0.01 to 15 mass %, based on the entiresolid content of the polymerizable composition.

[11] Filler

The polymerizable composition of the present invention may furthercontain a filler. The filler which can be used in the present inventionincludes spherical silica surface-treated with a silane coupling agent.

The polymerizable composition of the present preferably contains afiller, because a pattern having high durability is obtained (inparticular, when higher durability is required of the solder resist, forexample, when the wiring density of the metal wiring covered with asolder resist is high, the above-described effect is prominent).

By using spherical silica surface-treated with a silane coupling agent,the thermal cycle test resistance and storage stability of thepolymerizable composition are enhanced, and the same good profile asthat immediately after pattern formation can be maintained, for example,even through a severe atmosphere such as thermal cycle test.

The term “spherical” in the spherical filler may be sufficient if theparticle is not of a needle-like, columnar or amorphous shape but isrounded, and the shape need not be necessarily “truly spherical”.However, the typical “spherical” shape is “a truly spherical” shape.

Whether the filler is spherical can be confirmed by observing it thougha scanning electron microscope (SEM).

The volume average primary particle diameter of the filler is notparticularly limited and may be appropriately selected according to thepurpose but is preferably from 0.05 to 3 μm, more preferably from 0.1 to1 μm. When the volume average primary particle diameter of the filler isin the range above, this is advantageous in that impairment of theprocessability due to development of thixotropy is suppressed and themaximum particle diameter is kept from becoming large, as a result,generation of a defect due to attachment of extraneous material to thecured film obtained or non-uniformity of the coated film can beprevented.

The volume average primary particle diameter of the filler can bemeasured by a dynamic light scattering particle diameter distributionmeasuring apparatus.

The filler can be dispersed using the above-described dispersant andbinder. As stated earlier, in view of curability, an alkali-solublebinder having a crosslinking group in the side chain is preferred.

—Surface Treatment—

The surface treatment of the filler is described below. The surfacetreatment of the filler is not particularly limited and may beappropriately selected according to the purpose, but a treatment ofcovering silica with a silane coupling agent is preferred.

—Silane Coupling Agent—

The silane coupling agent used for the surface treatment of the filleris not particularly limited and may be appropriately selected accordingto the purpose, but at least one functional group selected from analkoxysilyl group, a chlorosilyl group and an acetoxysilyl group(hereinafter, sometimes referred to as a “first functional group”) andat least one functional group selected from a (meth)acryloyl group, anamino group and an epoxy group (hereinafter, sometimes referred to as a“second functional group). The second functional group is morepreferably a (meth)acryloyl group or an amino group, and it is stillmore preferred that the second functional group is a (meth)acryloylgroup. When the second functional group is a (meth)acryloyl group, thisis advantageous in view of storage stability and TCT resistance.

A coupling agent containing, as a first functional group, at least onemember selected from an alkoxysilyl group, a chlorosilyl group and anacetoxysilyl group and, as a second functional group, at least onemember selected from an imidazole group, an alkylimidazole group and avinylimidazole group, described in JP-B-7-68256, can be also preferablyused.

The silane coupling agent is not particularly limited, but preferredexamples thereof include a γ-aminopropyltriethoxysilane,N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane,N-(β-aminoethyl)-γ-aminopropylmethyldimethoxysilane,γ-glycidoxypropyltrimethoxysilane,γ-glycidoxypropylmethyldimethoxysilane,γ-methacryloxypropyltriethoxysilane,γ-methacryloxypropylmethyldimethoxysilane,α-[[3-(trimethoxysilyl)propoxy]methyl]-imidazole-1-ethanol described inJP-B-7-68256,2-ethyl-4-methyl-α-[[3-(trimethoxysilyl)propoxy]methyl]-imidazole-1-ethanol,4-vinyl-α-[[3-(trimethoxysilyl)propoxy]methyl]-imidazole-1-ethanol,2-ethyl-4-methylimidazopropyltrimethoxysilane, and their salts,intramolecular condensates and intermolecular condensates. One of thesecompounds may be used alone, or two or more thereof may be used incombination.

The surface treatment of spherical silica with the silane coupling agentmay be previously performed only for the spherical silica (in this case,hereinafter, sometimes referred to as a “pretreatment”) or may beperformed together with a part or all of other fillers contained in thepolymerizable composition.

The method for performing the pretreatment is not particularly limited,and examples of the method include a dry method, an aqueous solutionmethod, an organic solvent method and a spray method. The temperature atwhich the pretreatment is performed is not particularly limited but ispreferably from normal temperature to 200° C.

It is also preferred to add a catalyst when performing the pretreatment.The catalyst is not particularly limited, and examples thereof includean acid, a base, a metal compound, and an organic metal compound.

In the case of performing the pretreatment, the amount of the silanecoupling agent added is not particularly limited but is preferably from0.01 to 50 parts by mass, more preferably from 0.05 to 50 parts by mass,per 100 parts by mass of the spherical silica. When the amount added isin this range, a surface treatment sufficiently enough to develop theeffect is performed and at the same time, impairment of thehandleability due to aggregation of spherical silica after treatment isreduced.

The above-described silane coupling agent has an action of enhancing theadherence between the base material and the photosensitive layer,because the first functional group reacts with an active group in thebase material surface, spherical silica surface and binder and thesecond functional group reacts with a carboxyl group and anethylenically unsaturated group of the binder. On the other hand, thesilane coupling agent has high reactivity and if the silane couplingagent itself is added to the polymerizable composition, mainly thesecond functional group sometimes undergoes reaction or deactivationduring storage due to its diffusion action, giving rise to reduction inthe shelf life or pot life.

However, when spherical silica pretreated with a silane coupling agentis used, the diffusion action is suppressed to greatly improve theproblem of shelf life or pot life, and it is possible to take even aone-component system. Furthermore, in the case of applying thepretreatment to spherical silica, the conditions such as stirringcondition, temperature condition and use of catalyst can be freelyselected, so that compared to the addition without performing thepretreatment, the reaction ratio of the first functional group of thesilane coupling agent with an active group in the spherical silica canbe significantly increased. Accordingly, very good results are obtainedin terms of required characteristics under severe conditions such aselectroless gold plating, electroless solder plating and moistureresistance load test. Also, by performing the pretreatment, the amountof the silane coupling agent used can be decreased, and the shelf lifeand pot life can be more improved.

Examples of the spherical silica surface-treated with a silane couplingagent, which can be used in the present invention, include FB and SFPSeries of Denki Kagaku Kogyo Kabushiki Kaisha; 1-FX of Tatsumori Ltd.;HSP Series of Toagosei Co., Ltd.; and SP Series of Fuso Chemical Co.,Ltd.

The polymerizable composition may or may not contain a filler, but inthe case of containing a filler, the content thereof based on the entiresolid content by mass of the polymerizable composition is notparticularly limited and may be appropriately selected according to thepurpose. The content is preferably from 1 to 60 mass %. When the amountadded is in this range, sufficient reduction in the linear expansioncoefficient is achieved and at the same time, the cured film formed canbe kept from embrittlement, as a result, when wiring is formed using apermanent patter, the function as a protective film of the wiring isadequately exerted.

[12] Elastomer

The polymerizable composition of the present invention may furthercontain an elastomer.

By containing an elastomer, the adherence to the conductive layer of aprinted wiring board when using the polymerizable composition for asolder resist can be more improved and at the same time, heatresistance, thermal shock resistance, flexibility and toughness of thecured film can be more enhanced.

The elastomer which can be used in the present invention is notparticularly limited and may be appropriately selected according to thepurpose, and examples thereof include a styrene-based elastomer, anolefin-based elastomer, a urethane-based elastomer, a polyester-basedelastomer, a polyamide-based elastomer, an acrylic elastomer, and asilicone-based elastomer. Such an elastomer is composed of a hardsegment component and a soft segment component, where in general, theformer contributes to heat resistance and strength and the lattercontributes to flexibility and toughness. Among these, a polyester-basedelastomer is advantageous in view of compatibility with other materials.

Examples of the styrene-based elastomer include astyrene-butadiene-styrene block copolymer, a styrene-isoprene-styreneblock copolymer, a styrene-ethylene-butylene-styrene block copolymer,and a styrene-ethylene-propylene-styrene block copolymer. As thecomponent constituting the styrene-based elastomer, other than styrene,a styrene derivative such as α-methylstyrene, 3-methylstyrene,4-propylstyrene and 4-cyclohexylstyrene can be used. Specific examplesthereof include TUFPRENE, SOLPRENE T, ASAPRENE T, Tuftec (all producedby ADEKA), Elastomer AR (produced by Aronkasei Co., Ltd.), Kraton G,Califlex (both produced by Shell in Japan), JSR-TR, TSR-SIS, Dynaron(all produced by JSR), Denka STR (produced Denki Kagaku Kogyo K.K.),Quintac (produced by ZEON Corporation), TPE-SB Series (produced bySumitomo Chemical Co., Ltd.), Rabalon (produced by Mitsubishi ChemicalCorporation), Septon, HYBRAR (both produced by Kuraray Co., Ltd.),Sumiflex (produced by Sumitomo Bakelite Co., Ltd.), Leostomer, andActymer (both produced by Riken Vinyl Industry Co., Ltd.).

The olefin-based elastomer is a copolymer of α-olefin having a carbonnumber of 2 to 20, such as ethylene, propylene, 1-butene, 1-hexene and4-methyl-pentene, and examples thereof include an ethylene-propylenecopolymer (EPR) and an ethylene-propylene-diene copolymer (EPDM). Also,the olefin-based elastomer includes, for example, a copolymer of anα-olefin and a nonconjugated diene having a carbon number of 2 to 20,such as dicyclopentadiene, 1,4-hexadiene, cyclooctadiene,methylenenorbornene, ethylidenenorbornene, butadiene and isoprene, andan epoxidized polybutadiene. The olefin-based elastomer furtherincludes, for example, carboxyl-modified NBR obtained by copolymerizingmethacrylic acid with a butadiene-acrylonitrile copolymer. Otherexamples of the olefin-based elastomer include an ethylene-α-olefincopolymer rubber, an ethylene-α-olefin-nonconjugated diene copolymerrubber, a propylene-α-olefin copolymer rubber, and a butene-α-olefincopolymer rubber.

Specific examples of the olefin-based elastomer include Milastomer(produced by Mitsui Petrochemical Industries, Ltd.), EXACT (produced byExxon Chemical), ENGAGE (produced by Dow Chemical), hydrogenatedstyrene-butadiene rubber “DYNABON HSBR” (produced by JSR),butadiene-acrylonitrile copolymer “NBR Series” (produced by JSR),butadiene-acrylonitrile copolymer modified at both ends with a carboxylgroup having a crosslinking site “XER Series” (produced by JSR), andepoxidized polybutadiene obtained by partially epoxidizing polybutadiene“BF-1000” (produced by Nippon Soda Co., Ltd.).

The urethane-based elastomer consists of structural units, that is, ahard segment composed of low molecular (short chain) diol anddiisocyanate, and a soft segment composed of polymer (long chain) dioland diisocyanate. Examples of the polymer (long chain) diol includepolypropylene glycol, polytetramethylene oxide, poly(1,4-butyleneadipate), poly(ethylene-1,4-butylene adipate), polycaprolactone,poly(1,6-hexylene carbonate), and poly(1,6-hexylene-neopentyleneadipate). The number average molecular weight of the polymer (longchain) diol is preferably from 500 to 10,000. Examples of the lowmolecular (short chain) diol include ethylene glycol, propylene glycol,1,4-butanediol, and bisphenol A. The number average molecular weight ofthe short chain diol has is preferably from 48 to 500. Specific examplesof the urethane-based elastomer include PANDEX T-2185 and T-2983N (bothproduced by DIC Corporation), and Shirakutoran E790.

The polyester-based elastomer is obtained by polycondensing adicarboxylic acid or a derivative thereof and a diol compound or aderivative thereof. Specific examples of the dicarboxylic acid includean aromatic dicarboxylic acid such as terephthalic acid, isophthalicacid and naphthalenedicarboxylic acid; an aromatic dicarboxylic acidwhere a hydrogen atom of the above-described aromatic ring issubstituted with a methyl group, an ethyl group, a phenyl group or thelike; an aliphatic dicarboxylic acids having a carbon number of 2 to 20,such as adipic acid, sebacic acid and dodecanedicarboxylic acid; and analicyclic dicarboxylic acid such as cyclohexanedicarboxylic acid. One ofthese compounds or two or more thereof may be used. Specific examples ofthe diol compound include an aliphatic or alicyclic dial such asethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol,1,10-decanediol and 1,4-cyclohexanediol, bisphenol A,bis-(4-hydroxyphenyl)-methane, bis-(4-hydroxy-3-methylphenyl)-propane,and resorcin. One of these compounds or two or more thereof may be used.A multi-block copolymer using an aromatic polyester (e.g. polybutyleneterephthalate) moiety for the hard segment component and an aliphaticpolyester (e.g. polytetramethylene glycol) moiety for the soft segmentcomponent, can be used. The polyester-based elastomer includes variousgrades according to the kind, ratio and difference in the molecularweight of the hard segment and the soft segment. Specific examples ofthe polyester-based elastomer include Hytrel (produced by Du Pont-TorayCo., Ltd.), PELPRENE (produced by Toyobo Co., Ltd.), and ESPEL (producedby Hitachi Chemical Co., Ltd.).

The polyamide-based elastomer consists of a hard segment composed ofpolyamide and a soft segment composed of polyether or polyester and isroughly classified into two types, that is, a polyether block amide typeand a polyether ester block type. Examples of the polyamide includepolyamide-6, polyamide-11, and polyamide-12. Examples of the polyetherinclude polyoxyethylene, polyoxypropylene, and polytetramethyleneglycol. Specific examples of the polyamide-based elastomer include UBEPolyamide Elastomer (produced by Ube Industries, Ltd.), DAIAMID(produced by Daicel-Huels), PEBAX (produced by Toray Industries, Inc.),Grilon ELY (EMS Japan), Novamid (produced by Mitsubishi ChemicalCorporation), and Grilax (produced by DIC Corporation).

The acrylic elastomer is obtained by copolymerizing an acrylic acidester such as ethyl acrylate, butyl acrylate, methoxyethyl acrylate andethoxyethyl acrylate, an epoxy group-containing monomer such as glycidylmethacrylate and alkyl glycidyl ether, and/or a vinyl-based monomer suchas acrylonitrile and ethylene. Examples of the acrylic elastomer includean acrylonitrile-butyl acrylate copolymer, an acrylonitrile-butylacrylate-ethyl acrylate copolymer, and an acrylonitrile-butylacrylate-glycidyl methacrylate copolymer.

The silicone-based elastomer is mainly composed of an organopolysiloxaneand can be classified into a polydimethylsiloxane type, apolymethylphenylsiloxane type and a polydiphenylsiloxane type. Anorganopolysiloxane partially modified with a vinyl group, an alkoxygroup or the like may be also used. Specific examples of thesilicone-based elastomer include KE Series (produced by Shin-EtsuChemical Co., Ltd.), SE Series, CY Series and SH Series (all produced byDow Corning Toray Silicone Co., Ltd.).

Other than the elastomers described above, a rubber-modified epoxy resinmay be used. The rubber-modified epoxy resin is obtained by modifying apart or all of epoxy groups in the above-described bisphenol F-typeepoxy resin, bisphenol A-type epoxy resin, salicylaldehyde-type epoxyresin, phenol novolak-type epoxy resin, cresol novolak-type epoxy resinor the like with, for example, a both-terminal carboxylic acid-modifiedbutadiene-acrylonitrile rubber or a terminal amino-modified siliconerubber.

Among the elastomers, in view of shear adherence and thermal shockresistance, a both-terminal carboxyl group-modifiedbutadiene-acrylonitrile copolymer, and ESPEL that is a polyester-basedelastomer having a hydroxyl group (ESPEL 1612 and 1620, produced byHitachi Chemical Co., Ltd.), and epoxidized polybutadiene are preferred.

The polymerizable composition of the present invention may or may notcontain an elastomer, but in the case of containing an elastomer, thecontent thereof based on the entire solid content by mass of thepolymerizable composition is not particularly limited and may beappropriately selected according to the purpose. The content ispreferably from 0.5 to 30 mass %, more preferably from 1 to 10 mass %,still more preferably from 3 to 8 mass %, based on the solid content.When the content is in this preferred range, the shear adherence andthermal shock resistance can be advantageously more enhanced.

[13] Surfactant

From the standpoint of more enhancing the coatability, in thephotosensitive resin composition of to the present invention, varioussurfactants may be added. As the surfactant, a variety of surfactantssuch as fluorine-containing surfactant, nonionic surfactant, cationicsurfactant, anionic surfactant and silicone-containing surfactant may beused.

In particular, when the polymerizable composition of the presentinvention contains a fluorine-containing surfactant, the liquidcharacteristics (particularly, fluidity) of a coating solution preparedcan be more enhanced and therefore, uniformity of the coating thicknessand liquid saving performance can be more improved.

That is, in the case of forming a film by using a coating solution towhich a polymerizable composition containing a fluorine-containingsurfactant is applied, the interfacial tension between the surface to becoated and the coating solution is lowered, whereby wettability of thesurface to be coated is improved and coatability on the surface to becoated is enhanced. This is effective in that even when a thin film onthe order of several is formed with a small amount of solution, a filmbeing reduced in the thickness unevenness and having a uniform thicknesscan be more successfully performed.

The fluorine content of the fluorine-containing surfactant is preferablyfrom 3 to 40 mass %, more preferably from 5 to 30 mass %, still morepreferably from 7 to 25 mass %. The fluorine-containing surfactanthaving a fluorine content in this range is effective in view ofthickness uniformity of the coated film or liquid saving performance andalso exhibits good solubility in the polymerizable composition.

Examples of the fluorine-containing surfactant include Megaface F171,Megaface F172, Megaface F173, Megaface F176, Megaface F177, MegafaceF141, Megaface F142, Megaface F143, Megaface F144, Megaface R30,Megaface F437, Megaface F475, Megaface F479, Megaface F482, MegafaceF554, Megaface F780, Megaface F781 (all produced by DIC Corporation),Fluorad FC430, Fluorad FC431, Fluorad FC171 (all produced by Sumitomo 3MLtd.), Surflon S-382, Surflon SC-101, Surflon SC-103, Surflon SC-104,Surflon SC-105, Surflon SC-1068, Surflon SC-381, Surflon SC-383, SurflonS-393, Surflon KH-40 (all produced by Asahi Glass Co., Ltd.), andSoisperse 20000 (produced by The Lubrizol Corporation).

Specific examples of the nonionic surfactant include glycerol,trimethylolpropane, trimethylolethane, their ethoxylate and propoxylate(e.g., glycerol propoxylate, glycerin ethoxylate), polyoxyethylenelauryl ether, polyoxyethylene stearyl ether, polyoxyethylene oleylether, polyoxyethylene octylphenyl ether, polyoxyethylene nonylphenylether, polyethylene glycol dilaurate, polyethylene glycol distearate,and sorbitan fatty acid esters (such as Pluronic L10, L31, L61, L62,10R5, 17R2 and 25R2, and Tetronic 304, 701, 704, 901, 904 and 150R1,produced by BASF).

Specific examples of the cationic surfactant include a phthalocyaninederivative (EFKA-745, trade name, produced by Morishita Sangyo K.K.),organosiloxane polymer KP341 (produced by Shin-Etsu Chemical Co., Ltd.),(meth)acrylic acid (co)polymers POLYFLOW No. 75, No. 90 and No. 95(produced by Kyoeisha Chemical Co., Ltd.), and WO01 (produced by YushoCo., Ltd.).

Specific examples of the anionic surfactant include WO04, WO05 and WO17(produced by Yusho Co Ltd.).

Examples of the silicone-containing surfactant include “TORAY SILICONEDC3PA”, “TORAY SILICONE SH7PA”, “TORAY SILICONE DC11PA”, “TORAY SILICONESH21PA”, “TORAY SILICONE SH28PA”, “TORAY SILICONE SH29PA”, “TORAYSILICONE SH30PA” and “TORAY SILICONE SH8400” produced Dow Corning ToraySilicone Co., Ltd.; “TSF-4440”, “TSF-4300”, “TSF-4445”, “TSF-4460” and“TSF-4452” produced by Momentive Performance Materials Inc.; “KP341”,“KF6001” and “KF6002” produced by Shin-Etsu Silicone; and “BYK307”,“BYK-323” and “BYK-330” produced by BYK Chemie.

As the surfactant, one kind of a surfactant may be used, or two or morekinds of surfactants may be used in combination.

The polymerizable composition may or may not contain a surfactant, butin the case of containing a surfactant, the content thereof ispreferably from 0.001 to 1 mass %, more preferably from 0.01 to 0.1 mass%, based on the entire solid content by mass of the polymerizablecomposition of the present invention.

[14] Other Components

In the polymerizable composition of the present invention, in additionto the above-described essential components and preferred additives,other components may be appropriately selected and used according to thepurpose within the range not impairing the effects of the presentinvention.

Examples of other components which can be used in combination include athermal curing accelerator, a thermal polymerization inhibitor, aplasticizer, and a colorant (colored pigment or dyestuff). Furthermore,an adherence promoter to substrate surface and other auxiliary agents(for example, an electrically conductive particle, a filler, a defoamingagent, a flame retardant, a leveling agent, a release promoter, anantioxidant, a perfume, a surface tension adjusting agent and a chaintransfer agent) may be also used in combination.

By appropriately incorporating these components, the properties of thesolder resist, such as stability, photographic property and filmproperty, can be adjusted in a targeted manner.

The thermal polymerization inhibitor is described in detail, forexample, in paragraphs [0101] and [0102] of JP-A-2008-250074.

The plasticizer is described in detail, for example, in paragraphs[0103] and [0104] of JP-A-2008-250074.

The colorant is described in detail, for example, in paragraphs [0105]and [0106] of JP-A-2008-250074 and paragraphs [0038] and [0039] ofJP-A-2009-205029.

The adherence promoter is described in detail, for example, inparagraphs [0107] to of JP-A-2008-250074.

All of the additives described in these publications are usable for thepolymerizable composition of the present invention.

The solid content concentration of the thus-obtained polymerizablecomposition of the present invention is preferably from 5 to 90 mass %,more preferably from 20 to 80 mass %, and most preferably from 40 to 60mass %.

The use application of the polymerizable composition of the presentinvention is not particularly limited, but examples thereof include asolder resist, a light-blocking film for back surface of a siliconsubstrate in a solid-state imaging device, and a light-blocking film forwafer-level lens, with a solder resist being preferred.

In the case where the polymerizable composition of the present inventionis used for a solder resist, in order to form a coated film having arelatively large thickness, the solid content concentration ispreferably from 30 to 80 mass %, more preferably from 35 to 70 mass %,and most preferably from 40 to 60 mass %.

The viscosity of the polymerizable composition of the present inventionis preferably from 1 to 3,000 mPa·s, more preferably from 10 to 2,000mPa·s, and most preferably from 100 to 1,500 mPa·s.

In the case where the polymerizable composition of the present inventionis used for a solder resist, in view of thick film formability anduniform coatability, the viscosity is preferably from 10 to 3,000 mPa·s,more preferably from 500 to 1,500 mPa·s, and most preferably from 700 to1,400 mPa·s.

The present invention also relates to a photosensitive layer formed ofthe polymerizable composition of the present invention. Thephotosensitive layer is formed of the polymerizable composition of thepresent invention and therefore, is a photosensitive layer exhibitinghigh light-blocking effect in the infrared region and high lighttransparency in the visible region and being capable of forming apattern having a desired profile as well as excellent durability (forexample, durability against high temperature/high humidity, or adherenceto substrate). In addition, this is a photosensitive layer capable ofsuppressing development scum in the pattern formation on a coppersurface.

The present invention also relates to a permanent pattern formed usingthe polymerizable composition of the present invention. The permanentpattern of the present invention is obtained by applying exposure andalkali development to the photosensitive layer formed of thepolymerizable composition of the present invention and by virtue ofusing the polymerizable composition of the present invention, this is apattern exhibiting high light-blocking effect in the infrared region andhigh light transparency in the visible region and having a desiredprofile as well as excellent durability (for example, durability againsthigh temperature/high humidity, or adherence to substrate). In addition,this pattern is reduced in the development scum on a copper surface.

Furthermore, the present invention also relates to a pattern formingmethod comprising, in order, a step of forming a photosensitive layer byusing the polymerizable composition of the present invention, a step ofpattern-exposing the photosensitive layer to cure the exposed area, anda step of removing the unexposed area by alkali development to form apermanent pattern.

The method for forming a permanent pattern by using the polymerizablecomposition of the present invention is described in detail below byreferring, for example, a patterned solder resist. However, descriptionsregarding the kind and amount used of the solvent for preparation of acoating solution, the coating method of the coating solution, thethickness of the photosensitive layer, the exposure step or other steps,and the like are not limited to the application to a solder resist.Here, for example, a case of forming a photosensitive layer(polymerizable composition layer) by using the polymerizable compositionis described.

—Photosensitive Layer—

In order to form a patterned solder resist (solder resist pattern), aphotosensitive layer is first formed using the polymerizable compositionof the present invention. The photosensitive layer is not particularlylimited as long as it is a layer formed by containing the polymerizablecomposition, and the film thickness, laminate structure and the like canbe appropriately selected according to the purpose.

The method forming the photosensitive layer includes a method comprisingdissolving, emulsifying or dispersing the polymerizable composition ofthe present invention in water or a solvent to prepare a coatingsolution, applying the coating solution directly on a support, anddrying the coating to form the photosensitive layer.

The solvent for preparation of the coating solution is not particularlylimited and may be appropriately selected according to the purpose fromthose capable of uniformly dissolving or dispersing respectivecomponents of the polymerizable composition of the present invention.Examples thereof include alcohols such as methanol, ethanol, normalpropanol, isopropanol, normal butanol, secondary butanol and normalhexanol; ketones such as acetone, methyl ethyl ketone, methyl isobutylketone, cyclohexanone and diisobutyl ketone; esters such as ethylacetate, butyl acetate, normal amyl acetate, methyl sulfate, ethylpropionate, dimethyl phthalate, ethyl benzoate, propylene glycolmonomethyl ether acetate and methoxy propyl acetate; aromatichydrocarbons such as toluene, xylene, benzene and ethylbenzene;halogenated hydrocarbons such as carbon tetrachloride,trichloroethylene, chloroform, 1,1,1-trichloroethane, methylene chlorideand monochlorobenzene; ethers such as tetrahydrofuran, diethyl ether,ethylene glycol monomethyl ether, ethylene glycol monoethyl ether,1-methoxy-2-propanol and propylene glycol monomethyl ether;dimethylformamide, dimethylacetamide, dimethylsulfoxide and sulfolane.One of these solvents may be used alone, or two or more thereof may beused in combination. Also, a known surfactant may be added.

The method for applying the coating solution on a support is notparticularly limited and may be appropriately selected according to thepurpose, and examples thereof include a coating method using a spincoater, a slit spin coater, a roll coater, a die coater or a curtaincoater.

The conditions when drying the coating vary depending on respectivecomponents, the kind of solvent, the ratio used and the like but areusually a temperature of 60 to 150° C. and from 30 seconds to 15minutes.

The thickness of the photosensitive layer is not particularly limitedand may be appropriately selected according to the purpose but, forexample, is preferably from 1 to 100 μm, more preferably from 2 to 50μm, still more preferably from 4 to 30 μm.

(Solder Resist Pattern Forming Method)

The method for forming a solder resist permanent pattern by using thepolymerizable composition for solder resist of the present inventioncomprises at least a exposure step and usually, further comprises adevelopment step under conditions appropriately selected as needed andother steps. The term “exposure” as used in the present inventionincludes not only exposure to light at various wavelengths but alsoirradiation with radiation such as electron beam and i-line.

<Exposure Step>

The exposure step is a step of exposing the photosensitive layer formedof the polymerizable composition layer through a mask, and in this step,only the region irradiated with light is cured.

The exposure is preferably performed by the irradiation with radiation,and the radiation that can be used for exposure is preferably anelectron beam, KrF, ArF, ultraviolet ray such as g-line, h-line andi-line, or visible light. Among these, g-line, h-line and i-line arepreferred.

The exposure system includes, for example, stepper exposure and exposureusing a high-pressure mercury lamp.

The exposure dose is preferably from 5 to 3,000 mJ/cm², more preferablyfrom 10 to 2,000 mJ/cm², and most preferably from 50 to 1,000 mJ/cm².

<Other Steps>

Other steps are not particularly limited and may be appropriatelyselected according to the purpose. Examples thereof include a step ofsurface-treating a base material, a development step, a curing treatmentstep and a post-exposure step.

<Development Step>

Following the exposure step, alkali development (development step) isperformed, whereby the portion not irradiated with light in the exposurestep is dissolved out into an aqueous alkali solution. As a result, onlythe photocured portion remains, and a patterned solder resist havinglight-blocking effect is formed.

The developer is preferably an organic alkali developer that does notdamage the underlying circuit. The development temperature is usuallyfrom 20 to 40° C., and the development time is from 10 to 180 seconds.

As for the alkali used in the developer, for example, an aqueousalkaline solution obtained by diluting an organic alkaline compound suchas aqueous ammonia, ethylamine, diethylamine, dimethylethanolamine,tetramethylammonium hydroxide, tetraethylammonium hydroxide, choline,pyrrole, piperidine and 1,8-diazabicyclo-[5,4,0]-7-undecene with purewater to a concentration of generally from 0.001 to 10 mass %,preferably from 0.01 to 1 mass %, is used. In the case of using adeveloper composed of such an aqueous alkaline solution, the film afterdevelopment is generally washed (rinsed) with pure water.

<Curing Treatment Step>

The curing treatment step is a step of, after the development step isperformed, if desired, applying a curing treatment to the photosensitivelayer in the formed pattern, and by performing this treatment, themechanical strength of the permanent pattern is enhanced.

The curing treatment step is not particularly limited and may beappropriately selected according to the purpose, but examples thereofinclude an entire surface exposure treatment and an entire surfaceheating treatment.

The method for the entire surface exposure treatment includes, forexample, a method of, after the development step, exposing the entiresurface of the laminate having the patterned photosensitive layerformed. By the entire surface exposure, curing of the polymerizationcomponents in the polymerizable composition forming the photosensitivelayer is promoted, and cuing of the permanent pattern further proceeds,whereby the mechanical strength and durability are improved.

The apparatus used for performing the entire surface exposure is notparticularly limited and may be appropriately selected according to thepurpose. Preferred examples thereof include an UV exposure machine suchas ultrahigh-pressure mercury lamp.

The method for the entire surface heating treatment includes a methodof, after the development step, heating the entire surface of thelaminate having the patterned photosensitive layer formed. By the entiresurface heating, the film strength of the pattern is increased.

The heating temperature in the entire surface heating is preferably from120 to 250° C., more preferably from 120 to 250° C. When the heatingtemperature is 120° C. or more, the film strength is increased by theheating treatment, and when it is 250° C. or less, the film quality canbe prevented from becoming weak and brittle due to decomposition of theresin in the photopolymerizable composition.

The heating time in the entire surface heating is preferably from 3 to180 minutes, more preferably from 5 to 120 minutes.

The apparatus used for performing the entire surface heating is notparticularly limited and may be appropriately selected according to thepurpose from conventional apparatuses. Examples thereof include a dryoven, a hot plate and an IR heater.

The thus-formed patterned resist has an excellent infrared-blockingeffect and therefore, has a wide range of application. The polymerizablecomposition has an excellent light-blocking effect in the infraredregion and light transparency in the ultraviolet to visible region, sothat a pattern having an excellent profile can be formed. At the sametime, the pattern (cured film) formed has an excellent infrared-blockingeffect and in turn, is useful in forming a solder resist for a devicewith a photodiode having sensitivity even to the infrared region,particularly, a solid-state imaging device.

As described above, the polymerizable composition of the presentinvention is useful for the formation of not only a solder resist butalso a light-blocking film for back surface of a silicon substrate in asolid-state imaging device, or a light-blocking film for wafer-levellens.

In this way, the present invention also relates to a solid-state imagingdevice having a permanent pattern formed of the polymerizablecomposition of the present invention.

The solid-state imaging device according to an embodiment of the presentinvention is described below by referring to FIGS. 1 and 2, but thepresent invention is not limited the following specific example.

Incidentally, common numerical references are used for the portionscommon between FIG. 1 and FIG. 2.

Also, in the description, the “top”, “above” and “upper side” indicatethe side father from the silicon substrate 10, and the “bottom”, “below”and “lower side” indicate the side closer to the silicone substrate 10.

FIG. 1 is a schematic cross-sectional view showing a configuration of acamera module having a solid-state imaging device according to aspecific example of the one embodiment above.

In FIG. 1, the camera module 200 is connected to a circuit substrate 70as a package substrate through a solder ball 60 as a connection member.

In detail, the camera module 200 is configured to include a solid-stateimaging device substrate 100 having an imaging element part on the firstmajor surface of a silicon substrate, a glass substrate 30 (lighttransmitting substrate) disposed above the first major surface of thesolid-state imaging device substrate 100, an infrared cut filter 42disposed above the glass substrate 30, a lens holder 50 being disposedabove the glass substrate 30 and the infrared cut filter 42 and havingan imaging lens 40 in the internal space, and a light-blocking andelectromagnetic shield 44 disposed to surround the peripheries of thesolid-state imaging device substrate 100 and the glass substrate 30.Each member is bonded through an adhesive 20, 41, 43 or 45.

In the camera module 200, incident light hv from the outsidesequentially passes through the imaging lens 40, the infrared cut filter42 and the glass substrate 30 and reaches the imaging device part of thesolid-state imaging device substrate 100.

Also, the camera module 200 is connected to a circuit substrate 70through a solder ball 60 (connection material) on the second majorsurface side of the solid-state imaging device substrate 100.

FIG. 2 is a cross-sectional view on an enlarged scale showing thesolid-state imaging device substrate 100 in FIG. 1.

The solid-state imaging device substrate 100 is configured to include asilicon substrate 10 as a base body, an imaging element 12, aninterlayer insulating film 13, a base layer 14, a red color filter 15R,a green color filter 15G, a blue color filter 15B, an overcoat 16, amicrolens 17, a light-blocking film 18, an insulating film 22, a metalelectrode 23, a solder resist layer 24, an internal electrode 26, and adevice surface electrode 27.

The solder resist layer 24 may be omitted.

First, the configuration on the first major surface side of asolid-state imaging device substrate 100 is mainly described.

As shown in FIG. 2, an imaging element part where a plurality of imagingelements 12 such as CCD and CMOS are two-dimensionally arranged isprovided on the first major surface side of a silicon substrate 10 thatis the base body of the solid-state imaging device substrate 100.

An interlayer insulating film 13 is formed on the imaging element 12 inthe imaging element part, and a base layer 14 is formed on theinterlayer insulating film 13. Furthermore, a red color filter 15R, agreen color filter 15G and a blue color filter 15B (hereinaftersometimes collectively referred to as “color filter 15”) are disposed onthe base layer 14 to correspond to respective imaging elements 12.

A light-blocking film not shown may be provided in the boundaries of thered color filter 15R, the green color filter 15G and the blue colorfilter 15B and in the peripheries of the imaging element part. Thislight-blocking film can be produced, for example, by using a known blackcolor resist.

An overcoat 16 is formed on the color filter 15, and a microlens 17 isformed on the overcoat 16 to correspond to the imaging element 12 (colorfilter 15).

A peripheral circuit (not shown) and an internal electrode 26 areprovided in the periphery of the imaging element part on the first majorsurface side, and the internal electrode 26 is electrically connected tothe imaging element 12 through the peripheral circuit.

Furthermore, a device surface electrode 27 is formed on the internalelectrode 26 through the interlayer insulating film 13, and in theinterlayer insulating film 13 between the internal electrode 26 and thedevice surface electrode 27, a contact plug (not shown) for electricallyconnecting these electrodes is formed. The device surface electrode 27is used, for example, for applying a voltage or reading a signal throughthe contact plug and the internal electrode 26.

A base layer 14 is formed on the device surface electrode 27, and anovercoat 16 is formed on the base layer 14. The base layer 14 and theovercoat 16 formed on the deice surface electrode 27 are opened to forma pad opening part, and a part of the device surface electrode 27 isthereby exposed.

This is the configuration on the first major surface side of thesolid-state imaging device substrate 100.

On the first major surface side of the solid-state imaging devicesubstrate 100, an adhesive 20 is provided in the periphery of theimaging element part, and the solid-state imaging device substrate 100and the glass substrate 30 are bonded through the adhesive 20.

Also, the silicon substrate 10 has a through hole penetrating thesilicon substrate 10, and a through-electrode as a part of a metalelectrode 23 is provided inside the through hole. The imaging elementpart and a circuit substrate 70 are electrically connected by thethrough-electrode.

The configuration on the second major surface side of the solid-stateimaging device substrate 100 is mainly described below.

On the second major surface side, an insulating film 22 is formed overan area from the second major surface to the inner wall of the throughhole.

A metal electrode 23 patterned to extend from the region on the secondmajor surface of the silicon substrate 10 to the inside of the throughhole is provided on the insulating film 22. The metal electrode 23 is anelectrode for connection between the imaging element part in thesolid-state imaging device substrate 100 and a circuit substrate 70.

Out of this metal electrode 23, the portion formed inside the throughhole is the through-electrode. The through-electrode penetrates a partof the silicon substrate 10 and the interlayer insulating film to reachbelow the internal electrode 26 and electrically connected to theinternal electrode 26.

Furthermore, on the second major surface side, a solder resist layer 24(protective insulating film) covering the second major surface on whichthe metal electrode 23 is formed, and having an opening part exposing apart of the metal electrode 23, is provided.

In addition, on the second major surface side, a light-blocking film 18covering the second major surface on which the solder resist layer 24 isformed, and having an opening part exposing a part of the metalelectrode 23, is provided.

In this configuration, (1) a light-blocking solder resist layer wherethe light-blocking film 18 and the solder resist layer 24 are unitedinto a single layer may be formed of the polymerizable composition ofthe present invention, or (2) while the light-blocking layer 18 and thesolder resist layer 24 are separate layers, the light-blocking film 18may be formed of the polymerizable composition of the present invention(in this case, the solder resist layer may be formed of a known solderresist composition).

Incidentally, in FIG. 2, the light-blocking film 18 is patterned tocover a part of the metal electrode 23 and expose the remaining portionbut may be patterned to expose the entirety of the metal electrode 23(the same applies to the patterning of the solder resist layer 24).

Also, the solder resist layer 24 may be omitted, or the light-blockingfilm 18 may be formed directly on the second major surface where themetal electrode 23 is formed.

A solder ball 60 as a connection member is provided on the exposed metalelectrode 23, and the metal electrode 23 of the solid-state imagingdevice substrate 100 and the connection electrode not shown of thecircuit substrate 70 are electrically connected through the solder ball60.

In the above, the configuration of the solid-state device substrate 100is described, but each part except for the light-blocking film 18 of thesolid-state imaging device substrate 100 can be formed by a known methodsuch as method described in paragraphs 0033 to 0068 of JP-a-2009-158863and method described in paragraphs 0036 to 0065 of JP-A-2009-99591.

The light-blocking film 18 can be formed by the above-describedproduction method for the light-blocking film of the present invention.

The interlayer insulating film 13 is formed, for example, as an SiO₂film or an SiN film by sputtering, CVD (chemical vapor deposition) orthe like.

The color filter 15 is formed, for example, by photolithography using aknown color resist.

The overcoat 16 and the base layer 14 are formed, for example, byphotolithography using a known resist for organic interlayer filmformation.

The microlens 17 is formed, for example, by photolithography using astyrene-based resin or the like.

In the case where the solder resist layer 24 and the light-blockinglayer 18 are combined to form a light-blocking solder resist layer as asingle layer, the layer is preferably formed of the polymerizablecomposition of the present invention.

On the other hand, when the solder resist layer 24 and thelight-blocking film 18 are separate layers, the solder resist layer 24is preferably formed, for example, by photolithography using a knownsolder resist containing a phenolic resin, a polyimide-based resin or anamine-based resin.

The solder ball 60 is formed, for example, using Sn—Pb (eutectic),95Pb—Sn (high-lead high-melting-point solder) or a Pb-free solder suchas Sn—Ag, Sn—Cu and Sn—Ag—Cu. The solder ball 60 is formed, for example,as a sphere having a diameter of 100 to 1,000 μm (preferably a diameterof 150 to 700 μm).

The internal electrode 26 and the device surface electrode 27 are formedas a metal electrode such as Cu, for example, by CMP (chemicalmechanical polishing), photolithography or etching.

The metal electrode 23 is formed as a metal electrode such as Cu, Au,Al, Ni, W, Pt, Mo, Cu compound, W compound and Mo compound, for example,by sputtering, photolithography, etching or electrolytic plating. Themetal electrode 23 may be in a single-layer configuration or amultilayer configuration consisting of two or more layers.

The film thickness of the metal electrode 23 is, for example, from 0.1to 20 μm (preferably from 0.1 to 10 μm). The silicon substrate 10 is notparticularly limited, but a silicon substrate reduced in the thicknessby shaving the back surface of the substrate may be used. The thicknessof the substrate is not limited, but, for example, a silicon waferhaving a thickness of 20 to 200 μm (preferably from 30 to 150 μm) isused.

The through hole of the silicon substrate 10 is formed, for example, byphotolithography and RIE (reactive ion etching).

In the forgoing pages, the solid-state imaging device substrate 100 as aspecific example of the above-described one embodiment is described byreferring to FIGS. 1 and 2, but the one embodiment is not limited to themode of FIG. 1 and FIG. 2, and the configuration of the embodiment isnot particularly limited as long as it is a configuration having a metalelectrode and a light-blocking film on the back surface side.

Next, an example where the permanent pattern obtained using thepolymerizable composition of the present invention is applied to thelight-blocking film of a wafer-level lens is described below byreferring to the drawings.

FIG. 3 is a plan view showing one example of the configuration of awafer-level lens array having a plurality of wafer-level lenses.

As shown in FIG. 3, the wafer-level lens array has a substrate 410 andlenses 412 arranged on the substrate 410. here, in FIG. 3, a pluralityof lenses 412 are two-dimensionally arranged with respect to thesubstrate 410 but may be one-dimensionally arranged.

FIG. 4 is a cross-sectional view along line A-A in FIG. 3.

As shown in FIG. 4, in the waver-level lens array, a light-blocking film414 for preventing light transmission through a portion except for thelens 412 is provided between a plurality of lenses 412 arranged on thesubstrate 410.

The wafer-level lens is composed of one lens 412 present on thesubstrate 410 and a light-blocking film 414 provided in thecircumferential periphery thereof. The polymerizable composition of thepresent invention is used for formation of this light-blocking film 414.

The wafer-level lens is described below by referring, for example, to aconfiguration where, as shown in FIG. 3, a plurality of lenses 412 aretwo-dimensionally arranged with respect to a substrate 410.

The lens 412 is generally composed of the same material as the substrate410 and is molded integrally on the substrate 410 or is molded as aseparate structure and fixed on the substrate. Here, an example isdescribed, but the wafer-level lens is not limited to this embodimentand may take various embodiments such as a wafer-level lens having amultilayer structure or a wafer-level lens separated into a lens moduleby dicing.

The material forming the lens 412 includes, for example, glass. Thereare an abundant variety of glasses, and since glass having a highrefractive index can be selected, this is suitable as the material ofthe lens. Also, the glass is excellent in the heat resistance and hasthe advantage of withstanding the reflow mounting on an imaging unit orthe like.

Other materials for forming the lens 412 include a resin. The resin isexcellent in the processability and is suitable for simply andinexpensively forming a lens surface by a mold or the like.

In this case, an energy-curable resin is preferably used for formationof the lens 412. The energy-curable resin may be either a resin capableof curing by heat or a resin capable of curing by irradiation with anactive energy ray (for example, irradiation with heat, ultraviolet rayor electron beam).

As the energy-curable resin, all of known resins may be used, but inconsideration of reflow mounting of the imaging unit, a resin having arelatively high softening point, for example, a softening point of 200°C. or more is preferred. A resin having a softening point of 250° C. ormore is more preferred.

The mode and production of the wafer-level lens are specificallydescribed below by referring, for example, to the production method of awafer-level lens array based on FIGS. 5 to 10.

[Mode and Production (1) of Wafer-Level Lens]

—Formation of Lens—

The method for forming a lens 412 on a substrate 410 is described byreferring to FIG. 5 and FIGS. 6A to 6C.

FIG. 5 is a view showing how a molding material (indicated by M in FIG.5) as a resin composition for lens formation is supplied to a substrate410.

Also, FIGS. 6A to 6C are views showing the procedure of molding a lens412 on a substrate 410 by using a mold 460.

As shown in FIG. 5, a molding material M is dropped on a lens 412molding site of a substrate 410 by using a dispenser 450. Here, amolding material M in an amount corresponding to one lens 412 issupplied to one site to be fed.

After supplying the molding material M to the substrate 410, as shown inFIG. 6A, a mold 460 for molding lenses 412 is disposed on the substrate410 surface side to which the molding material M is supplied.

In the mold 460, concaves 462 for transferring the lens 412 shape areprovided according to the desired number of lenses 412.

As shown in FIG. 6B, the mold 460 is pressed against the moldingmaterial M on the substrate 410 to deform the molding material M alongthe lines of the concave 462 shape. In the state of the mold 460 beingpressed against the molding material M, when the molding material M is athermosetting resin or an ultraviolet-curable resin, the mold 460 isexternally irradiated with heat or ultraviolet ray to cure the moldingmaterial M.

After curing the molding material M, as shown in FIG. 6C, the substrate410 and lenses 412 are separated from the mold 460.

—Formation of Light-Blocking Film—

The method for forming a light-blocking film 414 in the circumferentialperiphery of the lens 412 is described below by referring to FIGS. 7A to7C.

FIGS. 7A to 7C are schematic cross-sectional views showing the processof providing a light-blocking film 414 on the substrate 410 havingmolded thereon lenses 412.

The method for forming the light-blocking film 414 includes alight-blocking coating layer forming step of coating the polymerizablecomposition of the present invention on a substrate 410 to form alight-blocking coating layer 414A (see, FIG. 7A), an exposure step ofpattern-exposing the light-blocking coating layer 414A through a mask470 (see, FIG. 7B), and a development step of developing thelight-blocking coating layer 414A after exposure to remove the uncuredarea and form a patterned light-blocking film 414 (see, FIG. 7C).

Incidentally, formation of the light-blocking film 414 can bearbitrarily performed before producing the lens 412 or after the lens412 is produced, but here, the method of performing the formation afterproduction of the lens 412 is described in detail.

The steps in the method of forming the light-blocking film 414 aredescribed below.

<Light-Blocking Coating Layer Forming Step>

In the light-blocking coating layer forming step, as shown in FIG. 7A, apolymerizable composition is coated on a substrate 410 to form alight-blocking coating layer 414A having low optical reflectance andbeing composed of the polymerizable composition. At this time, thelight-blocking coating layer 414A is formed to cover all of thesubstrate 410 surface and the lens surface 412 a and lens edge 412 bsurface of the lens 412.

The substrate 410 which can be used in this step is not particularlylimited. Examples thereof include soda glass, alkali-free glass, Pyrex(registered trademark) glass, quartz glass and transparent resin.

The substrate 410 as used herein indicates an embodiment containing boththe lens 412 and the substrate 410 in the case of integrally forming thelens 412 and the substrate 410.

On the substrate 410, if desired, an undercoat layer may be provided soas to improve adherence to an overlying layer, prevent diffusion of thematerial, or flatten the substrate 410 surface.

As the method for coating the polymerizable composition on the substrate410 and the lens 412, various coating methods such as slit coating,spray coating, inkjet printing, spin coating, cast coating, roll coatingand screen printing may be applied.

In view of thickness uniformity of the coated film and easy drying ofthe coating solvent, the film thickness immediately after coating of thepolymerizable composition is preferably from 0.1 to 10 μm, morepreferably from 0.2 to 5 μm, still more preferably from 0.2 to 3 μm.

Drying (prebaking) of the light-blocking coating layer 414A coated onthe substrate 410 may be performed using a hot plate, an oven or thelike at a temperature of 50 to 140° C. for 10 to 300 seconds.

The thickness of the coated film after drying of the polymerizablecomposition (hereinafter, sometimes referred to as “dry thickness”) maybe arbitrarily selected by taking into consideration the performancesuch as desired light-blocking effect and is generally from 0.1 μm toless than 50 μm.

<Exposure Step>

In the exposure step, the light-blocking coating layer 414A formed inthe light-blocking coating layer forming step is pattern-exposed. Thepattern exposure may be scanning exposure, but an embodiment of, asshown in FIG. 7B, performing the exposure through a mask 70 having apredetermined mask pattern is preferred.

As for the exposure in this step, the pattern exposure of thelight-blocking coating layer 414A is performed by exposure through apredetermined mask pattern, where only the portion irradiated with lightout of the light-blocking coating layer 414A is cured by the exposure.In this exposure, a mask pattern allowing for irradiation with light onthe lens edge 412 b surface and the substrate 410 surface between lenses412 is used. By using such a mask pattern, the light-blocking coatinglayer 414A only in the region excluding the lens surface 412 a is curedby the irradiation with light, and the cured region forms thelight-blocking film 414.

The radiation which can be used for exposure is preferably anultraviolet ray such as g-line, h-line and i-line. For this radiation, alight source having a single wavelength may be used, or a light sourcecontaining all wavelengths, such as high-pressure mercury lamp, may beused.

<Development Step>

Subsequently, alkali development (development step) is performed,whereby the portion not irradiated with light in the exposure, that is,the uncured region of the light-blocking coating layer 414A, isdissolved out into an aqueous alkali solution and only the region curedby the irradiation with light is allowed to remain.

Specifically, by developing the light-blocking coating layer 414Aexposed as shown in FIG. 7B, only the light-blocking coating layer 414Aformed on the lens surface 12 a is, as shown in FIG. 7C, removed and alight-blocking film 414 cured is formed in other regions.

As the alkali agent contained in the developer (aqueous alkalinesolution) used in the development step, all of an organic alkali agent,an inorganic alkali agent and a combination thereof may be used. For thelight-blocking film formation in the present invention, an organicalkali agent is preferably used, because it scarcely damages theneighboring circuit or the like.

Examples of the alkali agent used in the developer include an organicalkaline compound (organic alkali agent) such as aqueous ammonia,ethylamine, diethylamine, dimethylethanolamine, tetramethylammoniumhydroxide, tetraethylammonium hydroxide, choline, pyrrole, piperidineand 1,8-diazabicyclo-[5,4,0]-7-undecene, and an inorganic compound(inorganic alkali agent) such as sodium hydroxide, potassium hydroxide,sodium hydrogencarbonate and potassium hydrogencarbonate. An aqueousalkaline solution obtained by diluting such an alkali agent with purewater to a concentration of 0.001 to 10 mass %, preferably from 0.01 to1 mass %, is preferably used as the developer.

The development temperature is usually from 20 to 30° C., and thedevelopment time is from 20 to 90 seconds.

In the case of using a developer composed of such an aqueous alkalinesolution, after removing the unexposed area of the coated film with adeveloper, the film is generally washed (rinsed) with pure water. Thatis, after the development, the film is thoroughly washed with pure waterto remove the excess developer and then further subjected to a dryingstep.

Incidentally, after performing the above-described light-blockingcoating layer forming step, exposure step and development step, a curingstep of curing the formed light-blocking film (light-blocking pattern)by heating (post-baking) and/or exposure may be provided, if desired.

The post-baking is a heating treatment after development so as toachieve complete curing, and a thermal curing treatment usually at 100to 250° C. is performed. The conditions of post-baking, such astemperature and time, may be appropriately set according to the materialof the substrate 410 or lens 412. For example, when the substrate 412 isglass, out of the temperature range above, a temperature of 180 to 240°C. is preferably used.

This post-baking treatment is applied to the light-blocking film 414formed after development and can be performed in a continuous system ora batch system by using a heating device such as hot plate, convectionoven (hot air circulating drier) and high-frequency heater to establishthe above-described conditions.

The procedure above is described by referring, for example, a case wherethe lens 412 has a concave shape, but the shape is not particularlylimited and may be convex or aspheric. Also, the procedure above isdescribed by referring, for example, a wafer-level lens where aplurality of lenses 412 are molded on one surface of a substrate 410,but a configuration where a plurality of lenses 412 are molded on bothsurfaces of a substrate 410 may be also employed and in this case, thepatterned light-blocking film 414 is formed on both surfaces in theregions excluding lens surfaces.

[Mode and Production (2) of Wafer-Level Lens]

FIG. 8 is a view showing another configuration example of thewafer-level lens array.

The wafer-level lens shown in FIG. 8 is in a configuration (monolithictype) where the substrate 410 and the lens 412 are simultaneously moldedusing the same molding material.

As the molding material for the preparation of such a wafer-level lens,the same as those described above may be used. Also, in this example, aplurality of concave lenses 412 are formed on one surface (surface onthe upper side in the Figure) of a substrate 410, and a plurality ofconvex lenses 420 are formed on another surface (surface on the lowerside in the Figure). Furthermore, a patterned light-blocking film 414 isformed in the regions excluding lens surfaces 412 a of the substrate410, that is, formed on the substrate 410 surface and the lens edge 412b surface. As the patterning method when forming the light-blocking film414, the above-described procedure may be applied.

[Mode and Production (3) of Wafer-Level Lens]

Still another configuration example of the wafer-level lens array andthe production procedure therefor are described below by referring toFIGS. 9A to 9C and FIGS. 10A to 10C.

FIGS. 9A to 9C are schematic views showing another process of forming apatterned light-blocking film 414.

FIGS. 10A to 10C are schematic views showing the process of firstforming a patterned light-blocking film 414 and next molding a lens 412.

In the example of the wafer-level lens array shown in FIGS. 5 to 8, apatterned light-blocking film 414 is formed on a substrate 410 havingprovided thereon a lens 412, but in the following procedure, a patternedlight-blocking film 414 is first formed on a substrate 410 and a lens412 is then molded on the substrate 410.

—Formation of Light-Blocking Film—

As shown in FIG. 9A, first, a light-blocking coating layer forming stepof coating a polymerizable composition on a substrate 410 to form alight-blocking coating layer 414A is performed.

Thereafter, drying of the light-blocking coating layer 414A formed onthe substrate 410 is performed using a hot plate, an oven or the like ata temperature of 50 to 140° C. for 10 to 300 seconds. The dry thicknessof the polymerizable composition may be arbitrarily selected accordingto the performance such as desired light-blocking effect but isgenerally from 0.1 μm to less than 50 μm.

Next, as shown in FIG. 9B, an exposure step of patternwise exposing thelight-blocking coating layer 414A formed in the light-blocking coatinglayer forming step, through a mask 470 is performed. The mask 470 has apredetermined mask pattern.

In the exposure of this step, the light-blocking coating layer 414 ispattern-exposed, whereby only the portion irradiated with light out ofthe light-blocking coating layer 414A is cured. Here, a mask patternallowing for irradiation with light only on the light-blocking coatinglayer 414A in the region excluding the site working out to a lensopening 414 a of a lens 412 when the lens 412 is molded in the laterstep, is used. By this method, the light-blocking coating layer 414Aonly in the region excluding the site working out to a lens opening 414a of a lens 412 is cured by the irradiation with light. As for theradiation which can be used for the exposure, an ultraviolet ray such asg-line, h-line and i-line is preferably used, similarly to the proceduredescribed earlier.

Subsequently, alkali development (development step) is performed,whereby the light-blocking coating layer 414A only in the regioncorresponding to a lens opening 414 a of a lens 412, which is thelight-blocking coating layer 414A region uncured in the pattern exposureabove, is dissolved out into an aqueous alkali solution. At this time,as shown in FIG. 9C, the photocured light-blocking coating layer 414A inthe region excluding the region for a lens opening 414 a of a lens 412remains on the substrate 410 and forms a light-blocking film 414.

As for the alkali agent in the aqueous alkali solution that is thedeveloper, the same as in the procedure described earlier may be used.

After the development, the excess developer is removed by washing, andthe film is then dried.

Also in this embodiment, after performing the above-describedlight-blocking coating layer forming step, exposure step and developmentstep, a curing step of curing the formed light-blocking film bypost-baking and/or exposure may be provided, if desired.

The polymerizable composition of the present invention can be easilycleaned and removed with a known cleaning solution even when itattaches, for example, to a nozzle at the discharge port of the coatingapparatus, a piping area of the coating apparatus, or the interior ofthe coating apparatus. In this case, in order to more efficientlyperform the cleaning and removal, a solvent described above as thesolvent contained in the polymerizable composition of the presentinvention is preferably used for the cleaning solution.

Furthermore, cleaning solutions described, for example, inJP-A-7-128867, JP-A-7-146562, JP-A-8-278637, JP-A-2000-273370,JP-A-2006-85140, JP-A-2006-291191, JP-A-2007-2101, JP-A-2007-2102 andJP-A-2007-281523 may be also suitably used as the cleaning solution forcleaning and removing the polymerizable composition of the presentinvention.

As the cleaning solution, an alkylene glycol monoalkyl ether carboxylateor an alkylene glycol monoalkyl ether is preferably used.

One of these solvent usable as the cleaning solution may be used alone,or two or more thereof may be mixed and used.

In the case of mixing two or more solvents, a mixed solvent obtained bymixing a hydroxyl group-containing solvent and a hydroxyl group-freesolvent is preferred. The mass ratio between the hydroxylgroup-containing solvent and the hydroxyl group-free solvent is from1/99 to 99/1, preferably from 10/90 to 90/10, more preferably from 20/80to 80/20. The mixed solvent is preferably a mixed solvent of propyleneglycol monomethyl ether acetate (PGMEA, another name:1-methoxy-2-acetoxypropane) and propylene glycol monomethyl ether (PGME,another name: 1-methoxy-2-propanol) in a ratio of 60/40.

Incidentally, in order to enhance the permeability of the cleaningsolution into the polymerizable composition, a surfactant describedabove as the surfactant which can be incorporated into the polymerizablecomposition may be added to the cleaning solution.

—Formation of Lens—

A step of forming a lens 412 after the formation of the light-blockingfilm 414 is described below.

As shown in FIG. 10A, a molding material M constituting the lens 412 isdropped by a dispenser 450 on the substrate 410 having formed thereonthe patterned light-blocking film 414. The molding material M issupplied to cover the region corresponding to a lens opening 414 a of alens 412, including a part of the light-blocking film 414 edge adjacentto the opening.

After supplying the molding material M to the substrate 410, as shown inFIG. 10B, a mold 480 for molding lenses is disposed on the substrate 410surface side to which the molding material M is supplied. In the mold480, concaves 482 for transferring the lens 412 shape are providedaccording to the desired number of lenses 412.

The mold 480 is pressed against the molding material M on the substrate410 to deform the molding material M along the lines of the concaveshape. In the state of the mold 480 being pressed against the moldingmaterial M, when the molding material M is a thermosetting resin or anultraviolet-curable resin, the mold is externally irradiated with heator ultraviolet ray to cure the molding material M.

After curing the molding material M, the substrate 410 and lenses 412are separated from the mold 480 to obtain a wafer-level lens having, asshown in FIG. 10C, a patterned light-blocking film 414 on a substrate410.

In this way, the wafer-level lens may have not only a configurationwhere the patterned light-blocking film 414 is provided, as shown inFIG. 7, in the region excluding a lens surface 412 a of a lens 412, butalso a configuration where the light-blocking film 414 is provided, asshown in FIG. 10C, in the region excluding a lens opening 414 a of alens 412.

In the wafer-level lens, the light-blocking film 414 being patternwiseformed on at least one surface of the substrate 410 sufficiently blockslight in the regions excluding the lens surface 412 a or lens opening414 a of the 412 and at the same time, suppress the generation ofreflected light. Accordingly, when the wafer-level lens is applied to animaging module with a solid-state imaging device, a trouble such asghost or flare associated with reflected light can be prevented fromoccurring during imaging.

Also, the light-blocking film 414 is provided on the substrate surface,eliminating the need to fix a separate light-blocking member or the likeon the wafer-level lens, and the rise in the production cost can besuppressed.

Incidentally, in the case of a configuration where a structure with anuneven surface is provided around the lens, a trouble such as ghost maybe likely to occur due to reflection or diffusion of light incident onthe structure. To get rid of this trouble, when a configuration of, asshown in FIG. 7, providing a patterned light-blocking film 414 in theregion excluding a lens surface 412 a of a lens 412 is employed, lightcan be blocked except for the lens surface 412 a and the opticalperformance can be improved.

EXAMPLES

The present invention is described below by referring to Examples, butthe present invention is not limited to these Examples by any means.

<Preparation of Binder Solution A>

A 1,000 mL-volume three-neck flask was charged with 159 g of1-methoxy-2-propanol and heated to 85° C. under nitrogen flow, and asolution prepared by adding 63.4 g of benzyl methacrylate, 72.3 g ofmethacrylic acid and 4.15 g of V-601 (produced by Wako Pure ChemicalIndustries, Ltd.) to 159 g of 1-methoxy-2-propanol was added dropwisethereto over 2 hours. After the completion of dropwise addition, themixture was further heated for 5 hours to allow the reaction to proceed.

Subsequently, the heating was stopped, and a benzylmethacrylate/methacrylic acid copolymer (30/70 by mol) was obtained.

Thereafter, a 120.0 g portion of the copolymer solution was transferredto a 300 mL-volume three-neck flask, and 16.6 g of glycidyl methacrylateand 0.16 g of p-methoxyphenol were added and dissolved by stirring.After the dissolution, 3.0 g of triphenylphosphine was added, and themixture was heated to 100° C., thereby performing an addition reaction.Disappearance of glycidyl methacrylate was confirmed by gaschromatography, and heating was stopped. Furthermore, 38 g of1-methoxy-2-propanol was added to prepare Binder Solution A having anacid group content of 2 meq/g (acid value: 112 mgKOH/g), a crosslinkinggroup content of 2.23 meq/g, a weight average molecular weight of 24,000(in terms of polystyrene by GPC method) and a solid content of 46 mass%.

<Preparation of Binder Solution B>

In a 500 ml-volume three-neck round-bottom flask equipped with acondenser and a stirrer, an isocyanate compound shown below and twokinds of diol compounds shown below were dissolved in a molar ratioshown below in 100 ml of N,N-dimethylacetamide (the total molar amountof diisocyanate compound and two kinds of diol compound was 0.152 mol).Thereto, 0.1 g of dibutyltin dilaurate was added, and the mixture washeated with stirring at 100° C. for 8 hours. The resulting solution wasdiluted with 100 ml of N,N-dimethylformamide and 200 ml of methylalcohol and stirred for 30 minutes. The reaction solution was poured in3 liter of water with stirring to precipitate a white polymer. Thispolymer was separated by filtration, washed with water and dried undervacuum to obtain Urethane-Based Resin P-1. Subsequently,1-methoxy-2-propanol was added to the urethane-based resin to prepareBinder Solution B having an acid group content of 1.3 meq/g, acrosslinking group content of 1.59 meq/g, a weight average molecularweight of 15,000 (in terms of polystyrene by GPC method) and a solidcontent of 46 mass %.

Weight Average Polymer Molecular No. Diisocyanate Compound Used (mol %)Diol Compound Used (mol %) Weight P-1

15,000<Preparation of Binder Solution C>

A 1,000 mL-volume three-neck flask was charged with 159 g of1-methoxy-2-propanol and heated to 85° C. under nitrogen flow, and 159 gof a 1-methoxy-2-propanol solution containing 138 g of benzylmethacrylate and 4.15 g of V-601 (produced by Wako Pure ChemicalIndustries, Ltd.) was added dropwise thereto over 2 hours. After thecompletion of dropwise addition, the mixture was further heated for 5hours to allow the reaction to proceed.

Subsequently, the heating was stopped, and a benzyl methacrylate polymerwas obtained.

Thereafter, a 120.0 g portion of the copolymer solution above wastransferred to a 300 mL-volume three-neck flask, and 42.0 g of glycidylmethacrylate and 0.16 g of p-methoxyphenol were added and dissolved bystirring. After the dissolution, 3.0 g of triphenylphosphine was added,and the mixture was heated to 100° C., thereby performing an additionreaction. Disappearance of glycidyl methacrylate was confirmed by gaschromatography, and heating was stopped. Furthermore, 38 g of1-methoxy-2-propanol was added to prepare Binder Solution C having anacid group content of 0 meq/g (acid value: 0 mgKOH/g), a crosslinkinggroup content of 3.8 meq/g, a weight average molecular weight of 24,000(in terms of polystyrene by GPC method) and a solid content of 46 mass%.

Preparation of Polymerizable Composition Solution Example 1

The components in the following formulation were mixed to obtain thepolymerizable composition solution of Example 1. The viscosity of thecomposition was 1,060 mPa·s (the solid content concentration of thecomposition was 55 mass %).

Binder Solution A (alkali-soluble binder) 14.9 parts by massDipentaerythritol hexaacrylate (KAYARAD 7.72 parts by mass DPHA, tradename, produced by Nippon Kayaku Co., Ltd.) (polymerizable compound)Irgacure 907 (acetophenone-based compound 2.03 parts by mass produced byBASF Japan) (polymerization initiator) Kayacure DETX-S(thioxanthone-based 0.43 parts by mass compound produced by NipponKayaku Co., Ltd.) (sensitizer) Dispersion liquid shown below (filler,alkali- 45.09 parts by mass soluble binder) Megaface F-780 (produced byDIC 0.14 parts by mass Corporation) (surfactant) YMF-02 (produced bySumitomo Metal 26.97 parts by mass Mining Co., Ltd., cesium tungstenoxide (a 18.5 mass % dispersion liquid of Cs_(0.33)WO₃ (averagedispersed particle diameter: 800 nm or less))

As for the dispersion liquid above, 30 parts by mass of silica (SO—Cl,produced by Admatechs Company Limited) (filler) and 48.2 parts by massof Binder Solution A were previously mixed, the mixture was thendispersed by using zirconia beads having a diameter of 1.0 mm in a motormill M-250 (manufactured by Eiger) at a circumferential velocity of 9m/s for 3 hours, and the thus-prepared dispersion liquid was used.

Example 2

The composition of Example 2 was obtained according to the sameformulation as in Example 1 except that YMF-02 (produced by SumitomoMetal Mining Co., Ltd., a 18.5 mass % dispersion liquid of cesiumtungsten oxide Cs_(0.33)WO₃ (average dispersed particle diameter: 800 nmor less)) was replaced by KHF-7 (produced by Sumitomo Metal Mining Co.,Ltd., a dispersion liquid of lanthanum boride in a concentration of 3.5mass % (average particle diameter: 0.3 μm)). The viscosity of thecomposition of Example 2 was 600 mPa·s.

Example 3

The composition of Example 3 was obtained according to the sameformulation as in Example 1 except for further adding 0.09 parts by massof a compound represented by the following formula (ultravioletabsorber). The viscosity of the composition of Example 3 was 1,015mPa·s.

Example 4

The composition of Example 4 was obtained according to the sameformulation as in Example 1 except for replacing Kayacure DETX-S bycoumarin. The viscosity of the composition of Example 4 was 1,010 mPa·s.

Example 5

The composition of Example 5 was obtained according to the sameformulation as in Example 1 except for replacing Kayacure DETX-S by10-n-butyl-2-chloroacridone (NBCA, trade name, produced by KuroganeKasei Co., Ltd.). The viscosity of the composition of Example 5 was 980mPa·s.

Example 6

The composition of Example 6 was obtained according to the sameformulation as in Example 1 except for not using Kayacure DETX-S. Theviscosity of the composition of Example 6 was 990 mPa·s.

Example 7

The composition of Example 7 was obtained according to the sameformulation as in Example 1 except for replacing Irgacure 907 (producedby BASF Japan) by Irgacure 369 (acetophenone-based compound produced byBASF Japan). The viscosity of the composition of Example 7 was 880mPa·s.

Example 8

The composition of Example 8 was obtained according to the sameformulation as in Example 7 except for not using Kayacure DETX-S. Theviscosity of the composition of Example 8 was 890 mPa·s.

Example 9

The composition of Example 9 was obtained according to the sameformulation as in Example 1 except for replacing Irgacure 907 (producedby BASF Japan) by Irgacure 819 (acylphosphine oxide-based compoundproduced by BASF Japan). The viscosity of the composition of Example 9was 790 mPa·s.

Example 10

The composition of Example 10 was obtained according to the sameformulation as in Example 9 except for not using Kayacure DETX-S. Theviscosity of the composition of Example 10 was 830 mPa·s.

Example 11

The composition of Example 11 was obtained according to the sameformulation as in Example 1 except for replacing Irgacure 907 (producedby BASF Japan) by Lucirin TPO (acylphosphine oxide-based compoundproduced by BASF Japan). The viscosity of the composition of Example 11was 880 mPa·s.

Example 12

The composition of Example 12 was obtained according to the sameformulation as in Example 11 except for not using Kayacure DETX-S. Theviscosity of the composition of Example 12 was 790 mPa·s.

Example 13

The composition of Example 13 was obtained according to the sameformulation as in Example 1 except for replacing Irgacure 907 (producedby BASF Japan) by Lucirin TPO-L (acylphosphine oxide-based compoundproduced by BASF Japan). The viscosity of the composition of Example 13was 830 mPa·s.

Example 14

The composition of Example 14 was obtained according to the sameformulation as in Example 13 except for not using Kayacure DETX-S. Theviscosity of the composition of Example 14 was 820 mPa·s.

Example 15

The composition of Example 15 was obtained according to the sameformulation as in Example 1 except for replacing Binder Solution A(including Binder Solution A in the dispersion liquid) by BinderSolution B. The viscosity of the composition of Example 15 was 690mPa·s.

Example 16

The composition of Example 16 was obtained according to the sameformulation as in Example 1 except for replacing Binder Solution A(including Binder Solution A in the dispersion liquid) by Cyclomer P ACA230AA produced by DAICEL-CYTEC Company Ltd. (a 53 mass % propyleneglycol monomethyl ether solution). The viscosity of the composition ofExample 16 was 720 mPa·s.

Comparative Example 1

The composition of Comparative Example 1 was obtained according to thesame formulation as in Example 1 except for replacing YMF-02 by thefollowing Carbon Black Dispersion liquid A.

(Preparation of Carbon Black Dispersion Liquid A)

The components in Formulation I below were subjected to a high-viscositydispersion treatment using twin rolls to obtain a dispersion. At thistime, the viscosity of the dispersion was 70,000 mPa·s.

Thereafter, the mixture of Formulation II below was added to thedispersion, and these were stirred in a homogenizer under the conditionof 3,000 rpm for 3 hours. The obtained mixed solution was subjected to afine dispersion treatment for 4 hours in a disperser (Dispermat, tradename, manufactured by GETZMANN) using zirconia beads having a diameterof 0.3 mm to prepare Carbon Black Dispersion Liquid A. At this time, theviscosity of the mixed solution was 37 mPa·s.

(Formulation I)

Carbon black (Pigment Black 7) having an 23 parts by mass averageprimary particle diameter of 15 nm A propylene glycol monomethyl etheracetate 22 parts by mass 45 mass % solution of benzylmethacrylate/methacrylic acid copolymer (benzyl methacrylateunit/methacrylic acid unit = 67/33 (mol %), Mw: 28,000) Solsperse 5000(produced by The Lubrizol 1.2 parts by mass Corporation)(Formulation II)

A propylene glycol monomethyl ether acetate 22 parts by mass 45 mass %solution of benzyl methacrylate/methacrylic acid copolymer (benzylmethacrylate unit/methacrylic acid unit = 67/33 (mol %), Mw: 28,000)Propylene glycol monomethyl ether acetate 200 parts by mass

Comparative Example 2

The composition of Comparative Example 2 was obtained according to thesame formulation as in Example 1 except for not using Binder Solution A(including Binder Solution A in the dispersion liquid). The viscosity ofthe composition of Comparative Example 2 was 380 mPa·s.

Comparative Example 3

The composition of Comparative Example 3 was obtained according to thesame formulation as in Example 1 except for replacing Binder Solution A(including Binder Solution A in the dispersion liquid) by BinderSolution C. The viscosity of the composition of Comparative Example 3was 800 mPa·s.

<Evaluation of Polymerizable Composition for Solder Resist>

(Resist Pattern Formation)

Each of the polymerizable compositions obtained in Examples 1 to 16 andComparative Examples 1 to 3 was coated on a silicon wafer havingprovided on the surface thereof a copper layer (thickness: 10 μm)(hereinafter, sometimes referred to as a copper substrate), by a spincoating method to have a film thickness of 25 μm and then heated on ahot plate at 120° C. for 2 minutes to obtain a photosensitive layer.

The obtained photosensitive layer was irradiated with light in an i-linestepper through a photomask having a pattern of 300 μm in diameter bychanging the exposure dose in steps of 50 mJ/cm² in the range of 50 to2,000 mJ/cm².

The photosensitive laser after the exposure was subjected to puddledevelopment at 25° C. for 40 seconds by using an aqueous 2.38 mass %tetramethylammonium hydroxide solution, then rinsed by spin shower andfurther washed with pure water to obtain an infrared-blocking solderresist pattern. A minimum exposure dose (sensitivity) for obtaining acircle pattern of 50 μm in diameter when the development step wasperformed for 60 seconds, was measured and used as the index of patternformability. As the numerical value is smaller, the sensitivity andpattern formability are judged as better.

(Evaluations of Infrared-Blocking Effect and Visible Light Transparency)

The polymerizable composition was spin-coated on a glass substrate underthe conditions above to form a photosensitive layer (polymerizablecomposition layer) coating having a film thickness of 25 μm, and thetransmittance at a wavelength of 1,200 nm of the coating was measuredusing Ultraviolet-Visible-Near Infrared Spectrophotometer UV3600(manufactured by Shimadzu Corporation). As the numerical value issmaller, the infrared-blocking effect is judged as higher. When thetransmittance is 2% or less, the coating can be said to exhibit apractically good infrared-blocking effect.

Furthermore, the transmittance at a wavelength of 550 nm of the coatingabove was measured using Ultraviolet-Visible-Near InfraredSpectrophotometer UV3600 (manufactured by Shimadzu Corporation). As thenumerical value is larger, the visible light transparency is judged ashigher. When the transmittance of visible light is 30% or more, thecoating can be said to exhibit a practically good visible lighttransparency.

(Evaluation of Pattern Formability)

In accordance with (Resist Pattern Formation) above, exposure using aminimum exposure dose and development were performed to form a pattern.The pattern was observed using an electron microscope (S-4800,manufactured by Hitachi High-Technologies Corporation) and evaluatedaccording to the following evaluation standards. Here, in ComparativeExamples 1 to 3, since sufficient resolution was not obtained and theminimum exposure dose could not be calculated, exposure was performedwith an exposure dose of 800 mJ/cm².

[Evaluation Standards]

A: A pattern was formed on the copper substrate with sufficientadherence and the cross-section of the pattern showed a good rectangularshape. Also, in the unexposed area after development, almost nodevelopment scum was recognized on the copper substrate.B: A pattern was formed on the copper substrate as the substrate withsufficient adherence and the cross-section of the pattern showed a goodrectangular shape. Also, in the unexposed area after development,development scum was slightly recognized on the copper substrate but wasat a level not causing a problem in practice.C: A kind of a pattern was formed but adherence to the copper substratewas insufficient and a pattern stably adhering on the copper substratecould not be formed.CC: A pattern could not be resolved.(Evaluation of Durability Against High Temperature and High Humidity(Evaluation of Insulation Reliability): HAST Test)

On a silicon wafer as the base material, where wiring was formed in acomb form such that the copper thickness was 12 μM and the copperline/space was 50 μm/50 μm, each of the polymerizable compositions ofExamples 1 to 16 and Comparative Examples 1 to 3 was coated by a spincoating method to have a thickness of 20 μm on the copper. Thereafter,the coating was heated at 100° C. for 2 minutes on a hot plate to obtaina photosensitive layer.

The obtained photosensitive layer was irradiated with light of ahigh-pressure mercury lamp at the minimum exposure dose determined withrespect to each of Examples and Comparative Examples in (Resist PatternFormation) (however, in regards to Comparative Examples 1 to 3, theexposure was performed with an exposure dose of 800 mJ/cm², similarly tothe above).

The photosensitive laser after the exposure was subjected to puddledevelopment at 25° C. for 40 seconds by using an aqueous 2.38 mass %tetramethylammonium hydroxide solution, then rinsed by spin shower,further washed with pure water and thereafter, heat-treated(post-baking) at 150° C. for 1 hour to form a solder resist pattern(permanent pattern). The formed permanent pattern was subjected to aHAST test and evaluated for dendrite and insulation resistance (Ω). Inthe HAST test, with use of a high acceleration tester, a voltage of 10 Vwas applied to an electronic part module for 200 hours in an atmosphereof a temperature of 130° C. and a relative humidity of 85% and aftermeasuring the insulation resistance (Ω) of the conductor bump under thesame conditions, the conductor bump was observed for dendrite andevaluated as follows.

[Evaluation Standards]

AA: Absolutely no change in wiring.

A: Dendrite was not observed but anode wiring was slightly changed.

B: Dendrite was not observed but anode wiring was scarcely recognized.

C: Dendrite was observed.

The results of the evaluations above are shown in the Table below.

TABLE 1 Sensi- Insulation Visible tivity Reliability Infrared- Light(minimum L/S = 50 Pat- Blocking Trans- exposure μm/50 μm tern Effectparency dose) (10 V, Form- (1200 nm) (550 nm) (mJ/cm²) 200 hrs) abilityExample 1 <1% 51% 500 AA A Example 2 <1% 31% 500 AA A Example 3 <1% 52%500 AA A Example 4 <1% 51% 700 AA A Example 5 <1% 53% 600 AA A Example 6<1% 49% 800 AA A Example 7 <1% 50% 400 AA B Example 8 <1% 51% 800 AA BExample 9 <1% 52% 400 AA A Example 10 <1% 50% 800 AA A Example 11 <1%50% 600 AA A Example 12 <1% 54% 1200 AA B Example 13 <1% 48% 600 AA BExample 14 <1% 50% 1000 AA B Example 15 <1% 47% 600 AA A Example 16 <1%51% 300 AA A Compar- <1% <1% could could C ative not be not be Example 1evaluated evaluated Compar- <1% 35% could could CC ative not be not beExample 2 evaluated evaluated Compar- <1% 50% could could CC ative notbe not be Example 3 evaluated evaluated

As seen from the results of Table 1, according to the polymerizablecomposition of the present invention, a pattern satisfying all of (1)high light-blocking effect in the infrared region, (2) high lighttransparency in the visible region, and (3) desired profile andexcellent durability (for example, durability against hightemperature/high humidity, or adherence to substrate) by alkalidevelopment, could be formed. Also, it was revealed that developmentscum can be suppressed in the pattern formation on a copper surface.

On the other hand, in Comparative Examples 1 to 3, a pattern havingdesired profile and durability could no be obtained. Accordingly, inregard to Comparative Examples 1 to 3, the evaluation of insulationreliability could not be performed.

The entire disclosure of each and every foreign patent application fromwhich the benefit of foreign priority has been claimed in the presentapplication is incorporated herein by reference, as if fully set forth.

What is claimed is:
 1. A polymerizable composition comprising: (A) apolymerization initiator that is an acetophenone-based compound or anacylphosphine oxide-based compound, (B) a polymerizable compound, (C) atleast either a tungsten compound or a metal boride, and (D) analkali-soluble binder, and further comprising: a thioxanthone-basedcompound, and a silica filler.
 2. The polymerizable composition asclaimed in claim 1, wherein the composition further comprises at leastone solvent selected from the group consisting of propylene glycolmonomethyl ether acetate and 1-methoxy-2-propanol.
 3. The polymerizablecomposition as claimed in claim 1, wherein the content of the compound(C) is from 0.1 to 20 mass %, based on the entire solids content by massof the polymerizable composition.
 4. The polymerizable composition asclaimed in claim 1, wherein the content of the silica filler is from 1to 60 mass %.
 5. The polymerizable composition as claimed in claim 1,wherein the alkali-soluble binder has an acid group.
 6. Thepolymerizable composition as claimed in claim 1, wherein thealkali-soluble binder has a crosslinking group.
 7. The polymerizablecomposition as claimed in claim 1, wherein the alkali-soluble binder isa (meth)acrylic resin or a urethane-based resin.
 8. The polymerizablecomposition as claimed in claim 7, wherein the alkali-soluble binder isa urethane-based resin.
 9. The polymerizable composition as claimed inclaim 1, wherein the polymerizable composition contains a tungstencompound and the tungsten compound is represented by the followingformula (I):M_(x)W_(y)O_(z)  (I) wherein M represents a metal, W representstungsten, O represents oxygen,0.001≦x/y≦1.1,and2.2≦z/y≦3.0.
 10. The polymerizable composition as claimed in claim 9,wherein M is an alkali metal.
 11. The polymerizable composition asclaimed in claim 1, wherein the polymerizable composition contains ametal boride and the metal boride is at least one member selected fromthe group consisting of lanthanum boride, praseodymium boride, neodymiumboride, cerium boride, yttrium boride, titanium boride, zirconiumboride, hafnium boride, vanadium boride, tantalum boride, chromiumboride, molybdenum boride and tungsten boride.
 12. The polymerizablecomposition as claimed in claim 11, wherein the metal boride islanthanum boride.
 13. The polymerizable composition as claimed in claim1, wherein the polymerizable compound is a polyfunctional polymerizablecompound having a plurality of polymerizable groups within the molecule.14. The polymerizable composition as claimed in claim 1, which isutilized as a solder resist.
 15. The polymerizable composition asclaimed in claim 14, wherein the solids content concentration is from 30to 80 mass % and the viscosity at 25° C. is from 10 to 3,000 mPa·s. 16.A photosensitive layer formed of a polymerizable composition comprising:(A) a polymerization initiator which is an acetophenone-based compoundor an acylphosphine oxide-based compound, (B) a polymerizable compound,(C) at least either a tungsten compound or a metal boride, and (D) analkali-soluble binder, and further comprising: a thioxanthone-basedcompound, and a silica filler, wherein the transmittance of thephotosensitive layer at a wavelength of 1,200 nm is 2% or less and thetransmittance of the photosensitive layer at a wavelength of 550 nm is30% or more.
 17. A permanent pattern formed from a polymerizablecomposition comprising: (A) a polymerization initiator that is anacetophenone-based compound or an acylphosphine oxide-based compound,(B) a polymerizable compound, (C) at least either a tungsten compound ora metal boride, and (D) an alkali-soluble binder, and furthercomprising: a thioxanthone-based compound, and a silica filler, whereinthe transmittance of the permanent pattern at a wavelength of 1,200 nmis 2% or less and the transmittance of the permanent pattern at awavelength of 550 nm is 30% or more.
 18. The permanent pattern asclaimed in claim 17, wherein the permanent pattern is a solder resistlayer.
 19. The permanent pattern as claimed in claim 17, wherein thepermanent pattern is an infrared-blocking film.
 20. A polymerizablecomposition comprising: (A) a polymerization initiator that is anacetophenone-based compound or an acylphosphine oxide-based compound,(B) a polymerizable compound, (C) at least either a tungsten compound ora metal boride, and (D) an alkali-soluble binder, and furthercomprising: a thioxanthone-based compound, and a silica filler, whereinwhen a coating of the composition is formed, the transmittance of thecoating at a wavelength of 1,200 nm is 2% or less and the transmittanceof the coating at a wavelength of 550 nm is 30% or more.
 21. Thepolymerizable composition as claimed in claim 20, wherein thecomposition further comprises at least one solvent selected from thegroup consisting of propylene glycol monomethyl ether acetate and1-methoxy-2-propanol.
 22. The polymerizable composition as claimed inclaim 20, wherein the content of the compound (C) is from 0.1 to 20 mass%, based on the entire solids content by mass of the polymerizablecomposition.
 23. The polymerizable composition as claimed in claim 20,wherein the content of the silica filler is from 1 to 60 mass %.
 24. Thepolymerizable composition as claimed in claim 20, wherein thealkali-soluble binder has an acid group.
 25. The polymerizablecomposition as claimed in claim 20, wherein the alkali-soluble binderhas a crosslinking group.
 26. The polymerizable composition as claimedin claim 20, wherein the alkali-soluble binder is a (meth)acrylic resinor a urethane-based resin.
 27. The polymerizable composition as claimedin claim 26, wherein the alkali-soluble binder is a urethane-basedresin.
 28. The polymerizable composition as claimed in claim 20, whereinthe polymerizable composition contains a tungsten compound and thetungsten compound is represented by the following formula (I):M_(x)W_(y)O_(z)  (I) wherein M represents a metal, W representstungsten, O represents oxygen,0.001≦x/y≦1.1,and2.2≦z/y≦3.0.
 29. The polymerizable composition as claimed in claim 28,wherein M is an alkali metal.
 30. The polymerizable composition asclaimed in claim 20, wherein the polymerizable composition contains ametal boride and the metal boride is at least one member selected fromthe group consisting of lanthanum boride, praseodymium boride, neodymiumboride, cerium boride, yttrium boride, titanium boride, zirconiumboride, hafnium boride, vanadium boride, tantalum boride, chromiumboride, molybdenum boride and tungsten boride.
 31. The polymerizablecomposition as claimed in claim 30, wherein the metal boride islanthanum boride.
 32. The polymerizable composition as claimed in claim20, wherein the polymerizable compound is a polyfunctional polymerizablecompound having a plurality of polymerizable groups within the molecule.33. The polymerizable composition as claimed in claim 20, which isutilized as a solder resist.
 34. The polymerizable composition asclaimed in claim 33, wherein the solids content concentration is from 30to 80 mass % and the viscosity at 25° C. is from 10 to 3,000 mPa·s.